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Irrigation regimes modulate non-structural carbohydrate remobilization and improve grain filling in rice(Oryza sativa L.)by regulating starch metabolism 被引量:1
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作者 Yuguang Zang Gaozhao Wu +10 位作者 Qiangqiang Li Yiwen Xu Mingming Xue Xingyu Chen Haiyan Wei Weiyang Zhang Hao Zhang Lijun Liu Zhiqin Wang Junfei Gu Jianchang Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1507-1522,共16页
Recently developed ‘super’ rice cultivars with greater yield potentials often suffer from the problem of poor grain filling, especially in inferior spikelets. Here, we studied the activities of enzymes related to st... Recently developed ‘super’ rice cultivars with greater yield potentials often suffer from the problem of poor grain filling, especially in inferior spikelets. Here, we studied the activities of enzymes related to starch metabolism in rice stems and grains, and the microstructures related to carbohydrate accumulation and transportation to investigate the effects of different water regimes on grain filling. Two ‘super’ rice cultivars were grown under two irrigation regimes of well-watered(WW) and alternate wetting and moderate soil drying(AWMD). Compared with the WW treatment,the activities of ADP glucose pyrophosphorylase(AGPase), starch synthase(StSase) and starch branching enzyme(SBE), and the accumulation of non-structural carbohydrates(NSCs) in the stems before heading were significantly improved, and more starch granules were stored in the stems in the AWMD treatment. After heading, the activities of α-amylase, β-amylase, sucrose phosphate synthase(SPS) and sucrose synthase in the synthetic direction(SSs)were increased in the stems to promote the remobilization of NSCs for grain filling under AWMD. During grain filling, the enzymatic activities of sucrose synthase in the cleavage direction(SSc), AGPase, StSase and SBE in the inferior spikelets were increased, which promoted grain filling, especially for the inferior spikelets under AWMD.However, there were no significant differences in vascular microstructures. The grain yield and grain weight could be improved by 13.1 and 7.5%, respectively, by optimizing of the irrigation regime. We concluded that the low activities of key enzymes in carbon metabolism is the key limitation for the poor grain filling, as opposed to the vascular microstructures, and AWMD can increase the amount of NSC accumulation in the stems before heading, improve the utilization rate of NSCs after heading, and increase the grain filling, especially in the inferior spikelets, by altering the activities of key enzymes in carbon metabolism. 展开更多
关键词 rice(Oryza sativa L.) non-structural carbohydrates(NsCs) enzymatic activity grain illing starch granules vascular bundle
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Experimental investigation on weak shock wave mitigation characteristics of flexible polyurethane foam and polyurea 被引量:1
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作者 Shiyu Jia Cheng Wang +2 位作者 Wenlong Xu Dong Ma Fangfang Qi 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期179-191,共13页
In recent years,explosion shock wave has been considered as a signature injury of the current military conflicts.Although strong shock wave is lethal to the human body,weak shock wave can cause many more lasting conse... In recent years,explosion shock wave has been considered as a signature injury of the current military conflicts.Although strong shock wave is lethal to the human body,weak shock wave can cause many more lasting consequences.To investigate the protection ability and characteristics of flexible materials and structures under weak shock wave loading,the blast wave produced by TNT explosive is loaded on the polyurethane foam with the density of 200.0 kg/m3(F-200)and 400.0 kg/m3(F-400),polyurea with the density of 1100.0 kg/m^(3)(P-1100)and structures composed of the two materials,which are intended for individual protection.Experimental results indicate that the shock wave is attenuated to weak pressure disturbance after interacting with the flexible materials which are not damaged.The shock wave protective capability of single-layer materials is dependent on their thickness,density and microscopic characteristics.The overpressure,maximum pressure rise rate and impulse of transmitted wave decrease exponentially with increase in sample thickness.For the same thickness,F-400 provides better protective capability than F-200 while P-1100 shows the best protective capability among the three materials.In this study,as the materials are not destroyed,F-200 with a thickness more than10.0 mm,F-400 with a thickness more than 4.0 mm,and P-1100 with a thickness more than 1.0 mm can attenuate the overpressure amplitude more than 90.0%.Further,multi-layer flexible composites are designed.Different layer layouts of designed structures and layer thickness of the single-layer materials can affect the protective performance.Within the research range,the structure in which polyurea is placed on the impact side shows the optimal shock wave protective performance,and the thicknesses of polyurea and polyurethane foam are 1.0 mm and 4.0 mm respectively.The overpressure attenuation rate reached maximum value of 93.3%and impulse attenuation capacity of this structure are better than those of single-layer polyurea and polyurethane foam with higher areal density. 展开更多
关键词 Free-field explosion Weak shock wave mitigation POLYUREA Polyurethane foam Multi-layered composites
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Cooperative Anti-Jamming and Interference Mitigation for UAV Networks: A Local Altruistic Game Approach 被引量:1
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作者 Yueyue Su Nan Qi +2 位作者 Zanqi Huang Rugui Yao Luliang Jia 《China Communications》 SCIE CSCD 2024年第2期183-196,共14页
To improve the anti-jamming and interference mitigation ability of the UAV-aided communication systems, this paper investigates the channel selection optimization problem in face of both internal mutual interference a... To improve the anti-jamming and interference mitigation ability of the UAV-aided communication systems, this paper investigates the channel selection optimization problem in face of both internal mutual interference and external malicious jamming. A cooperative anti-jamming and interference mitigation method based on local altruistic is proposed to optimize UAVs’ channel selection. Specifically, a Stackelberg game is modeled to formulate the confrontation relationship between UAVs and the jammer. A local altruistic game is modeled with each UAV considering the utilities of both itself and other UAVs. A distributed cooperative anti-jamming and interference mitigation algorithm is proposed to obtain the Stackelberg equilibrium. Finally, the convergence of the proposed algorithm and the impact of the transmission power on the system loss value are analyzed, and the anti-jamming performance of the proposed algorithm can be improved by around 64% compared with the existing algorithms. 展开更多
关键词 channel selection cooperative antijamming and interference mitigation local altruistic game Stackelberg game unmanned aerial vehicle(UAV)
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Effects of drought on non-structural carbohydrates and C,N,and P stoichiometric characteristics of Pinus yunnanensis seedlings
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作者 Zhijuan Zhao Lina Wang +7 位作者 Yuanxi Liu Jianli Sun Jiandong Xiao Qiong Dong Lianfang Li Wanjie Zhang Chao Wang Junwen Wu 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期90-102,共13页
To study non-structural carbohydrate character-istics and nutrient utilization strategies of Pinus yunnanen-sis under continuous drought conditions,2-year-old seed-lings were planted in pots with appropriate water,lig... To study non-structural carbohydrate character-istics and nutrient utilization strategies of Pinus yunnanen-sis under continuous drought conditions,2-year-old seed-lings were planted in pots with appropriate water,light and moderate and severe drought treatments[(80±5),(65±5),(50±5),and(35±5)%of field water-holding capacity].Non-structural carbohydrates,carbon(C),nitrogen(N),and phosphorus(P)concentrations were measured in each plant component.The results show that:(1)With increasing drought,non-structural carbohydrates gradually increased in leaves,stems,and coarse roots,while gradually decreased in fine roots;(2)C concentrations of all were relatively stable under different stress levels.Phosphorous utilization of each component increased under light and moderate drought conditions,while N and P utilization efficiency of each plant component decreased under severe drought.Growth was mainly restricted by N,first decreasing and then increasing with increased drought;(3)There was a correlation between the levels of non-structural carbohydrates and C,N,and P in each component.Changes in N concentration affected the interconversion between soluble sugar and starch,which play a regulatory role in the fluctuation of the concentration of non-structural carbohydrates;and,(4)Plasticity analysis showed that P.yunnanensis seedlings responded to drought mainly by altering starch concentration,the ratio of soluble sugar to starch in leaves and stems,and further by alter-ing N and P utilization efficiencies.Overall,these results suggest that the physiological activities of all organs of P.yunnanensis seedlings are restricted under drought and that trade-offs exist between different physiological indicators and organs.Our findings are helpful in understanding non-structural carbohydrate and nutrient adaptation mechanisms under drought in P.yunnanensis seedlings. 展开更多
关键词 Pinus yunnanensis seedlings DROUGHT non-structural carbohydrates C N P stoichiometric characteristics
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Comparing trends of crop and pasture in future land-use scenarios for climate change mitigation
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作者 Maxime Malbranque Xiangping Hu Francesco Cherubini 《Geography and Sustainability》 CSCD 2024年第3期470-481,共12页
Revegetation of former agricultural land is a key option for climate change mitigation and nature conservation.Expansion and abandonment of agricultural land is typically influenced by trends in diets and agricultural... Revegetation of former agricultural land is a key option for climate change mitigation and nature conservation.Expansion and abandonment of agricultural land is typically influenced by trends in diets and agricultural inten-sification,which are two key parameters in the Shared Socioeconomic Pathways(SSPs).Datasets mapping future land dynamics under different SSPs and climate change mitigation targets stem from different scenario assump-tions,land data and modelling frameworks.This study aims to determine the role that these three factors play in the estimates of the evolution of cropland and pastureland in future SSPs under different climate scenarios from four main datasets largely used in the climate and land surface studies.The datasets largely agree with the rep-resentation of cropland at present-day conditions,but the identification of pastureland is ambiguous and shows large discrepancies due to the lack of a unique land-use category.Differences occur with future projections,even for the same SSP and climate target.Accounting for CO_(2)sequestration from revegetation of abandoned agri-cultural land and CO_(2)emissions from forest clearance due to agricultural expansion shows a net reduction in vegetation carbon stock for most SSPs considered,except SSP1.However,different datasets give differences in estimates,even when representative of the same scenario.With SSP1,the cumulative increase in carbon stock until 2050 is 3.3 GtC for one dataset,and more than double for another.Our study calls for a common classifica-tion system with improved detection of pastureland to harmonize projections and reduce variability of outcomes in environmental studies. 展开更多
关键词 Natural forest regrowth Scenarios AGRICULTURE Climate change mitigation
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Impacts of Defoliation on Morphological Characteristics and Non-Structural Carbohydrates of Populus talassica × Populus euphratica Seedlings
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作者 Mengxu Su Zhanjiang Han +2 位作者 Zhen Zhao Xiaofeng Wu Jiaju Wu 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第7期1689-1703,共15页
Leaves are important‘source’organs that synthesize organic matter,providing carbon sources for plant growth.Here,we used Populus talassica×Populus euphratica,the dominant species in ecological and timber forest... Leaves are important‘source’organs that synthesize organic matter,providing carbon sources for plant growth.Here,we used Populus talassica×Populus euphratica,the dominant species in ecological and timber forests,to simulate carbon limitation through artificial 25%,50%,and 75%defoliation treatments and explore the effects on root,stem,and leaf morphology,biomass accumulation,and carbon allocation strategies.At the 60th d after treat-ment,under 25%defoliation treatment,the plant height,specific leaf weight,root surface area and volume,and concentrations of non-structural carbohydrates in stem and root were significantly increased by 9.13%,20.00%,16.60%,31.95%,5.12%,and 9.34%,respectively,relative to the control.There was no significant change in the growth indicators under 50%defoliation treatment,but the concentrations of non-structural carbohydrates in the leaf and stem significantly decreased,showing mostly a negative correlation between them.The opposite was observed in the root.Under 75%defoliation treatment,the plant height,ground diameter,leaf number,single leaf area,root,stem,and total biomass were significantly reduced by 14.15%,10.24%,14.86%,11.31%,11.56%,21.87%,and 16.82%,respectively,relative to the control.The concentrations of non-structural carbohydrates in various organs were significantly reduced,particularly in the consumption of the starch concentrations in the stem and root.These results indicated that carbon allocation strategies can be adjusted to increase the con-centration of non-structural carbohydrates in root and meet plant growth needs under 25%and 50%defoliation.However,75%defoliation significantly limited the distribution of non-structural carbohydrates to roots and stems,reduced carbon storage,and thus inhibited plant growth.Defoliation-induced carbon limitation altered the carbon allocation pattern of P.talassica×P.euphratica,and the relationship between carbon reserves in roots and tree growth recovery after defoliation was greater.This study provides a theoretical basis for the comprehen-sive management of P.talassica×P.euphratica plantations,as well as a reference for the study of plantation car-bon allocation strategies in the desert and semi-desert regions of Xinjiang under carbon-limitation conditions. 展开更多
关键词 Populus talassica×Populus euphratica DEFOLIATION carbon limitation carbon allocation non-structural carbohydrates
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Socio-scientific quantification of the comprehensive benefits of debris flow mitigation measures for villages in western Sichuan, China
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作者 DENG Ting XU Pei +4 位作者 LI Ming LU Yafeng WANG Yukuan LI Zhengyang SHRAVAN Kumar Ghimire 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1598-1612,共15页
Debris flow hazards seriously threaten thesafety and sustainable development of mountainousareas. Numerous debris flow mitigation measures havebeen implemented worldwide;however, acomprehensive assessment of the speci... Debris flow hazards seriously threaten thesafety and sustainable development of mountainousareas. Numerous debris flow mitigation measures havebeen implemented worldwide;however, acomprehensive assessment of the specific disasterreduction effects of these measures and their economic,social and ecological benefits is yet to be performed.The western region of Sichuan Province frequentlysuffers from geohazards such as debris flow, and thegovernment has adopted many mitigation measures.This study assessed the benefits of debris flowmitigation measures and identified the key influencingfactors via a field-based study conducted in 81 villagesin western Sichuan province, China. A framework forthe evaluation of the benefits of rural debris flowmitigation measures was constructed andquantitatively evaluated using a survey. Snowballsampling was performed to recruit 81 village leadersand 468 farmers. The results showed that managementand engineering measures were the main methodsused to mitigate debris flow;ecological measures wereauxiliary. The average satisfaction scores of farmers forthese three types of measures were 4.07, 3.90, and 3.56,respectively (as measured on a five-point Likert scale).In contrast, in terms of the benefits of these mitigationmeasures, only a small proportion of villages (11.11%)obtained a high level of comprehensive benefits fromthe debris flow mitigation measures, while the majority(88.89%) received medium to low-level benefits. Toimprove this situation, we further studied and foundthat the main factors that restricted villages fromachieving high-level comprehensive benefits were theunpredictable nature of debris flows, labour forceoutflow and remoteness. Effective control measures, agood economic environment and strong governmentassistance were reported as crucial factors forimproving these comprehensive benefits. This studyprovides socio-scientific references for decisionmakingon rural debris flow mitigation measures while keeping villages at the centre of economic development. 展开更多
关键词 mitigation measures Comprehensive benefit evaluation Debris flow Mountain development Rural areas
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Overview on Mangrove Forest Disaster Prevention and Mitigation Functions
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作者 CHEN Xinping YIN Ziqi +6 位作者 LI Zibin WANG Bin TAO Aifeng GUO Zhixing WANG Fei AN Yanhong O’DRISCOLL Kieran 《Journal of Ocean University of China》 CAS CSCD 2024年第1期46-56,共11页
This paper provides a comprehensive overview on coastal protection and hazard mitigation by mangroves.Previous stud-ies have made great strides to understand the mechanisms and influencing factors of mangroves’protec... This paper provides a comprehensive overview on coastal protection and hazard mitigation by mangroves.Previous stud-ies have made great strides to understand the mechanisms and influencing factors of mangroves’protection function,including wave energy dissipation,storm surge damping,tsunami mitigation,adjustment to sea level rise and wind speed reduction,which are sys-tematically summarized in this study.Moreover,the study analyzes the extensive physical models,based on indoor flume experi-ments and numerical models,that consider the interaction between mangroves and hydrodynamics,to help our understanding of mangrove-hydrodynamic interactions.Additionally,quantitative approaches for valuing coastal protection services provided by man-groves,including index-based and process-resolving approaches,are introduced in detail.Finally,we point out the limitations of previous studies,indicating that efforts are still required for obtaining more long-term field observations during extreme weather events,to create more real mangrove models for physical experiments,and to develop numerical models that consider the flexible properties of mangroves to better predict wave propagation in mangroves having complex morphology and structures. 展开更多
关键词 MANGROVE coastal protection disaster prevention and mitigation disaster reduction value coastal resilience
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Mitigation of polycyclic aromatic hydrocarbons(PAHs)in roasted beef patties by cold plasma treatment and products quality evaluation
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作者 Yuke Hou Yangjian Hu +8 位作者 Min Li Jiahui Nong Fengyuan Xie Yuhan Fan Jianhao Zhang Xianming Zeng Minyi Han Xinglian Xu Xia Wang 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2993-3005,共13页
The cold plasma(CP)technique was applied to alleviate the contamination of polycyclic aromatic hydrocarbon(PAH)in this investigation.Two different CP treatments methods were implemented in the production of beef patti... The cold plasma(CP)technique was applied to alleviate the contamination of polycyclic aromatic hydrocarbon(PAH)in this investigation.Two different CP treatments methods were implemented in the production of beef patties,to investigate their inhibition and degradation capacity on PAHs.With 5 different cooking oils and fats addition,the inhibition mechanism of in-package cold plasma(ICP)pretreatment was explored from the aspect of raw patties fatty acids composition variation.The results of principal component analysis showed that the first two principal components accounted for more than 80%of the total variation in the original data,indicating that the content of saturated fatty acids was significantly positively correlated with the formation of PAHs.ICP pretreatment inhibited the formation of PAHs by changing the composition of fatty acids,which showed that the total amount of polyunsaturated fatty acids decreased and the total amount of monounsaturated fatty acids increased.Sensory discrimination tests demonstrated there were discernable differences between 2 CP treated samples and the controls,utilization of the ICP pretreatment in meat products processing was expected to achieve satisfying eating quality.In conclusion,CP treatment degraded PAHs through stepwise ring-opening oxidation in 2 reported pathways,the toxicity of PAHs contaminated products was alleviated after CP treatment. 展开更多
关键词 Roasted beef Polycyclic aromatic hydrocarbons Cold plasma mitigation mechanism Product quality evaluation
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Uncertainty and sensitivity analysis of in-vessel phenomena under severe accident mitigation strategy based on ISAA-SAUP program
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作者 Hao Yang Ji-Shen Li +2 位作者 Zhi-Ran Zhang Bin Zhang Jian-Qiang Shan 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期108-123,共16页
The phenomenology involved in severe accidents in nuclear reactors is highly complex.Currently,integrated analysis programs used for severe accident analysis heavily rely on custom empirical parameters,which introduce... The phenomenology involved in severe accidents in nuclear reactors is highly complex.Currently,integrated analysis programs used for severe accident analysis heavily rely on custom empirical parameters,which introduce considerable uncertainty.Therefore,in recent years,the field of severe accidents has shifted its focus toward applying uncertainty analysis methods to quantify uncertainty in safety assessment programs,known as“best estimate plus uncertainty(BEPU).”This approach aids in enhancing our comprehension of these programs and their further development and improvement.This study concentrates on a third-generation pressurized water reactor equipped with advanced active and passive mitigation strategies.Through an Integrated Severe Accident Analysis Program(ISAA),numerical modeling and uncertainty analysis were conducted on severe accidents resulting from large break loss of coolant accidents.Seventeen uncertainty parameters of the ISAA program were meticulously screened.Using Wilks'formula,the developed uncertainty program code,SAUP,was employed to carry out Latin hypercube sampling,while ISAA was employed to execute batch calculations.Statistical analysis was then conducted on two figures of merit,namely hydrogen generation and the release of fission products within the pressure vessel.Uncertainty calculations revealed that hydrogen production and the fraction of fission product released exhibited a normal distribution,ranging from 182.784 to 330.664 kg and from 15.6 to 84.3%,respectively.The ratio of hydrogen production to reactor thermal power fell within the range of 0.0578–0.105.A sensitivity analysis was performed for uncertain input parameters,revealing significant correlations between the failure temperature of the cladding oxide layer,maximum melt flow rate,size of the particulate debris,and porosity of the debris with both hydrogen generation and the release of fission products. 展开更多
关键词 Gen-III PWR Severe accident mitigation Wilks’formula HYDROGEN Fission products Uncertainty and sensitivity analysis
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On the Polygonal Wear Evolution of Heavy-Haul Locomotive Wheels due to Wheel/Rail Flexibility and Its Mitigation Measures
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作者 Yunfan Yang Feifan Chai +3 位作者 Pengfei Liu Liang Ling Kaiyun Wang Wanming Zhai 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第1期40-61,共22页
Wheel polygonal wear can immensely worsen wheel/rail interactions and vibration performances of the train and track,and ultimately,lead to the shortening of service life of railway components.At present,wheel/rail med... Wheel polygonal wear can immensely worsen wheel/rail interactions and vibration performances of the train and track,and ultimately,lead to the shortening of service life of railway components.At present,wheel/rail medium-or high-frequency frictional interactions are perceived as an essential reason of the high-order polygonal wear of railway wheels,which are potentially resulted by the flexible deformations of the train/track system or other external excitations.In this work,the effect of wheel/rail flexibility on polygonal wear evolution of heavy-haul locomotive wheels is explored with aid of the long-term wheel polygonal wear evolution simulations,in which different flexible modeling of the heavy-haul wheel/rail coupled system is implemented.Further,the mitigation measures for the polygonal wear of heavy-haul locomotive wheels are discussed.The results point out that the evolution of polygonal wear of heavy-haul locomotive wheels can be veritably simulated with consideration of the flexible effect of both wheelset and rails.Execution of mixed-line operation of heavy-haul trains and application of multicut wheel re-profiling can effectively reduce the development of wheel polygonal wear.This research can provide a deep-going understanding of polygonal wear evolution mechanism of heavy-haul locomotive wheels and its mitigation measures. 展开更多
关键词 Heavy-haul locomotive Wheel polygonal wear Wheel/rail flexibility Long-term polygonal wear evolution mitigation measures
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Parametric investigation of railway fastenings into the formation and mitigation of short pitch corrugation
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作者 Pan Zhang Shaoguang Li +1 位作者 Rolf Dollevoet Zili Li 《Railway Engineering Science》 EI 2024年第3期286-306,共21页
Short pitch corrugation has been a problem for railways worldwide over one century.In this paper,a parametric investigation of fastenings is conducted to understand the corrugation formation mechanism and gain insight... Short pitch corrugation has been a problem for railways worldwide over one century.In this paper,a parametric investigation of fastenings is conducted to understand the corrugation formation mechanism and gain insights into corrugation mitigation.A three-dimensional finite element vehicle-track dynamic interaction model is employed,which considers the coupling between the structural dynamics and the contact mechanics,while the damage mechanism is assumed to be differential wear.Various fastening models with different configurations,boundary conditions,and parameters of stiffness and damping are built up and analysed.These models may represent different service stages of fastenings in the field.Besides,the effect of train speeds on corrugation features is studied.The results indicate:(1)Fastening parameters and modelling play an important role in corrugation formation.(2)The fastening longitudinal constraint to the rail is the major factor that determines the corrugation formation.The fastening vertical and lateral constraints influence corrugation features in terms of spatial distribution and wavelength components.(3)The strengthening of fastening constraints in the longitudinal dimension helps to mitigate corrugation.Meanwhile,the inner fastening constraint in the lateral direction is necessary for corrugation alleviation.(4)The increase in fastening longitudinal stiffness and damping can reduce the vibration amplitudes of longitudinal compression modes and thus reduce the track corrugation propensity.The simulation in this work can well explain the field corrugation in terms of the occurrence possibility and major wavelength components.It can also explain the field data with respect to the small variation between the corrugation wavelength and train speed,which is caused by frequency selection and jump between rail longitudinal compression modes. 展开更多
关键词 Short pitch corrugation Fastening modelling and parameters Corrugation formation and mitigation Rail longitudinal compression modes Finite element vehicle-track interaction model
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Systematic Literature Review on Cloud Computing Security: Threats and Mitigation Strategies
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作者 Sina Ahmadi 《Journal of Information Security》 2024年第2期148-167,共20页
Cloud computing plays a significant role in modern information technology, providing organizations with numerous benefits, including flexibility, scalability, and cost-efficiency. However, it has become essential for ... Cloud computing plays a significant role in modern information technology, providing organizations with numerous benefits, including flexibility, scalability, and cost-efficiency. However, it has become essential for organizations to ensure the security of their applications, data, and cloud-based networks to use cloud services effectively. This systematic literature review aims to determine the latest information regarding cloud computing security, with a specific emphasis on threats and mitigation strategies. Additionally, it highlights some common threats related to cloud computing security, such as distributed denial-of-service (DDoS) attacks, account hijacking, malware attacks, and data breaches. This research also explores some mitigation strategies, including security awareness training, vulnerability management, security information and event management (SIEM), identity and access management (IAM), and encryption techniques. It discusses emerging trends in cloud security, such as integrating artificial intelligence (AI) and machine learning (ML), serverless computing, and containerization, as well as the effectiveness of the shared responsibility model and its related challenges. The importance of user awareness and the impact of emerging technologies on cloud security have also been discussed in detail to mitigate security risks. A literature review of previous research and scholarly articles has also been conducted to provide insights regarding cloud computing security. It shows the need for continuous research and innovation to address emerging threats and maintain a security-conscious culture in the company. 展开更多
关键词 Cloud Security Threat Analysis mitigation Strategies Emerging Trends Ethi-cal Considerations Data Analysis
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Optimization of Stealthwatch Network Security System for the Detection and Mitigation of Distributed Denial of Service (DDoS) Attack: Application to Smart Grid System
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作者 Emmanuel S. Kolawole Penrose S. Cofie +4 位作者 John H. Fuller Cajetan M. Akujuobi Emmanuel A. Dada Justin F. Foreman Pamela H. Obiomon 《Communications and Network》 2024年第3期108-134,共27页
The Smart Grid is an enhancement of the traditional grid system and employs new technologies and sophisticated communication techniques for electrical power transmission and distribution. The Smart Grid’s communicati... The Smart Grid is an enhancement of the traditional grid system and employs new technologies and sophisticated communication techniques for electrical power transmission and distribution. The Smart Grid’s communication network shares information about status of its several integrated IEDs (Intelligent Electronic Devices). However, the IEDs connected throughout the Smart Grid, open opportunities for attackers to interfere with the communications and utilities resources or take clients’ private data. This development has introduced new cyber-security challenges for the Smart Grid and is a very concerning issue because of emerging cyber-threats and security incidents that have occurred recently all over the world. The purpose of this research is to detect and mitigate Distributed Denial of Service [DDoS] with application to the Electrical Smart Grid System by deploying an optimized Stealthwatch Secure Network analytics tool. In this paper, the DDoS attack in the Smart Grid communication networks was modeled using Stealthwatch tool. The simulated network consisted of Secure Network Analytic tools virtual machines (VMs), electrical Grid network communication topology, attackers and Target VMs. Finally, the experiments and simulations were performed, and the research results showed that Stealthwatch analytic tool is very effective in detecting and mitigating DDoS attacks in the Smart Grid System without causing any blackout or shutdown of any internal systems as compared to other tools such as GNS3, NeSSi2, NISST Framework, OMNeT++, INET Framework, ReaSE, NS2, NS3, M5 Simulator, OPNET, PLC & TIA Portal management Software which do not have the capability to do so. Also, using Stealthwatch tool to create a security baseline for Smart Grid environment, contributes to risk mitigation and sound security hygiene. 展开更多
关键词 Smart Grid System Distributed Denial of Service (DDoS) Attack Intrusion Detection and Prevention Systems DETECTION mitigation and Stealthwatch
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Multi-disciplinary seismic resilience modeling for developing mitigation policies and recovery planning
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作者 Milad Roohi Saeid Ghasemi +5 位作者 Omar Sediek Hwayoung Jeon John W.van de Lindt Martin Shields Sara Hamideh Harvey Cutler 《Resilient Cities and Structures》 2024年第2期66-84,共19页
The multi-disciplinary data and information available at a community level comprise the foundation of natural hazard resilience modeling.These data enable and inform mitigation and recovery planning decisions prior to... The multi-disciplinary data and information available at a community level comprise the foundation of natural hazard resilience modeling.These data enable and inform mitigation and recovery planning decisions prior to and following damaging events such as earthquakes.This paper presents a multi-disciplinary seismic resilience mod-eling methodology to assess the vulnerability of the built environment and economic systems.This methodology can assist decision-makers with developing effective mitigation policies to improve the seismic resilience of com-munities.Two complementary modeling strategies are designed to examine the impacts of scenario earthquakes from a combined engineering and economic perspective.The engineering model is developed using a probabilis-tic fragility-based modeling approach and is analyzed using Monte Carlo(MC)simulations subject to seismic multi-hazard,including simulated ground shaking and resulting liquefaction of the soil,to quantify the physical damage to buildings and electric power substations(EPS).The outcome of the analysis is subsequently used as input to repair and recovery models to quantify repair cost and recovery time metrics for buildings and as input to functionality models to estimate the functionality of individual buildings and substations by accounting for their interdependency.The economic model consists of a spatial computable general equilibrium(SCGE)model that aggregates commercial buildings into sectors for retail,manufacturing,services,etc.,and aggregates residential buildings into a wide range of household groups.The SCGE model employs building functionality estimates to quantify the economic losses.The outcomes of this integrated modeling consist of engineering and economic impact metrics,which are used to investigate mitigation actions to help inform a community on approaches to achieve its resilience goals.An illustrative case study of Salt Lake County(SLC),Utah,developed through an extensive collaborative partnership and engagement with SLC officials,is presented.The results demonstrate the effectiveness of the proposed methodology in quantifying the loss and functional recovery of infrastructure systems,the impacts on capital stock,employment,and household income and the effect of various mitigation strategies in reducing the losses and functional recovery time subject to earthquakes with varying intensities. 展开更多
关键词 Community resilience Infrastructure systems MULTI-DISCIPLINARY mitigation policy Functional recovery
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Investigation of effects of hazard geometry and mitigation strategies on community resilience under tornado hazards using an Agent-based modeling approach
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作者 Xu Han Maria Koliou 《Resilient Cities and Structures》 2024年第2期1-19,共19页
A large number of communities are impacted annually by the increasing frequency of tornado hazards resulting in damage to the infrastructure as well as disruption of community functions.The effect of the hazard geomet... A large number of communities are impacted annually by the increasing frequency of tornado hazards resulting in damage to the infrastructure as well as disruption of community functions.The effect of the hazard geometry(center and angle of tornado path as well as the tornado width)is studied herein on how it influences the recovery of physical and social systems within the community.Given that pre-disaster preparedness including mitigation strategies(e.g.,retrofits)and policies(e.g.,insurance)is crucial for increasing the resilience of the community and facilitating a faster recovery process,in this study,the impact of various mitigation strategies and policies on the recovery trajectory and resilience of a typical US community subjected to a tornado is investigated considering different sources of uncertainties.The virtual testbed of Centerville is selected in this paper and is modeled by adopting the Agent-based modeling(ABM)approach which is a powerful tool for conducting community resilience analysis that simulates the behavior of different types of agents and their interactions to capture their interdependencies.The results are presented in the form of recovery time series as well as calculated resilience indices for various community systems(lifeline networks,schools,healthcare,businesses,and households).The results of this study can help deepen our understanding of how to efficiently expedite the recovery process of a community. 展开更多
关键词 Community resilience Agent-based modeling(ABM) TORNADO mitigation strategy
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Rockburst risk control and mitigation in deep mining
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作者 Ming Cai 《Deep Resources Engineering》 2024年第2期46-67,共22页
It is important to understand and manage rockburst challenges in deep mining operations.This paper presents a systematic study of rockburst risk in underground mining,offering a detailed examination of influencing fac... It is important to understand and manage rockburst challenges in deep mining operations.This paper presents a systematic study of rockburst risk in underground mining,offering a detailed examination of influencing factors,risk assessment,and various control and mitigation methods.The complexities of rockburst phenomena are explained by examining factors that lead to the occurrence of rockbursts.A rockburst risk assessment using a bow-tie analysis is conducted,which provides insights into both risk evaluation and proactive control and mitigation systems.The core of the paper presents a comprehensive array of rockburst risk control and mitigation methods,which range from controls to reduce rockburst hazard,and excavation vulnerability,to controls and mitigations to reduce exposure.Strategic engineering control methods,including mine design and mining sequencing,are discussed.Tactical engineering control measures,such as ground pre-conditioning and rock support,are scrutinized,along with administrative controls like evacuation and re-entry protocols and the use of mechanized equipment.A multiple-line defense system is advocated for rockburst risk management to address the uncertainties involved in the process.Finally,emerging technologies and innovations as well as challenges are discussed,providing a roadmap for continued advancements in rockburst risk management in the future.This work serves as a valuable resource for mining professionals,researchers,and policymakers seeking a comprehensive understanding of rockburst risk management in deep mining. 展开更多
关键词 Rockburst risk Rockburst hazard Excavation vulnerability Exposure Rock support Risk control Risk mitigation
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Wind risk and mitigation calculator framework for determining the wind annualized risk for single- and multi-family homes to support resilient community decision-making
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作者 Ayat Al Assi Rubayet Bin Mostafiz +6 位作者 Fatemeh Orooji Arash Taghinezhad Melanie Gall Robert V.Rohli Christopher T.Emrich Carol J.Friedland Eric Johnson 《Resilient Cities and Structures》 2024年第4期21-33,共13页
Communicating risks and mitigation benefits associated with natural hazards such as wind to the general public is challenging given the location-dependency of parameters and the complexity of the problem.Web tools pla... Communicating risks and mitigation benefits associated with natural hazards such as wind to the general public is challenging given the location-dependency of parameters and the complexity of the problem.Web tools play a crucial role in educating residents,decision-makers,and stakeholders regarding potential wind hazard losses to,for example,residential buildings.However,a notable gap exists on the practical incorporation of mitigation actions within these tools.This gap hampers the collective awareness and understanding among stakeholders,communities,and citizens regarding the tangible advantages of mitigation strategies in reducing wind-related risks.Furthermore,there exists a need to elucidate the functionality and objectives of these tools in a more accessible manner.This study aims to present and outline the wind risk and mitigation calculator tool(WRMCT)within the Hazardaware platform,which is an address-based risk assessment tool.This tool,developed for 196 counties in the Gulf of Mexico coastal area,facilitates users’education of potential risks and benefits associated with mitigation strategies.WRMCT enables users to access location-specific wind risk and interactively suggests potential mitigation actions along with economic savings to support informed decisions and residential risk reduction.WRMCT intends to enhance users’ability to make informed decisions,take proactive measures in mitigating wind hazards,and contribute to the development of resilient,residential communities. 展开更多
关键词 Wind risk assessment Average annual loss(AAL) Public information technology Wind mitigation Wind loss analysis Catastrophic risk modeling Resilient communities
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Study on the Changes of Non-structural Carbohydrates and Nitrogen Contents of Quercus aquifolioides Scrub along Different Elevation Gradient 被引量:2
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作者 黄亚洲 吴杰 +3 位作者 孟玉山 吕俊 王三根 朱万泽 《Agricultural Science & Technology》 CAS 2011年第4期576-580,共5页
[Objective] The aim was to compare the content changes between the non-structural carbohydrates(NSC)and the total nitrogen in various growing seasons,and to explore the response relationship between altitude and the... [Objective] The aim was to compare the content changes between the non-structural carbohydrates(NSC)and the total nitrogen in various growing seasons,and to explore the response relationship between altitude and the contents.[Method] Taking Quercus aquifolioides scrub which widely distributed in Zheduoshan in the west of Sichuan as the experimental objects,the changes between NSC and the toal nitrogen in various growing seasons at different altitude were studied.[Result] The results showed that the content of NSC in Quercus aquifolioides underground increased with the lift of elevation in the dormancy,but decreased in the early germination,growing period and growth stage.The content of NSC in the ground tissue changed non-linearly with increasing elevation.In addition,the total nitrogen of Quercus aquifolioides organizations was decreasing with increasing elevation in the dormant period,which did not change significantly in the other periods.This result implied that the content of NSC in Quercus aquifolioides underground was more sensitive to temperature.[Conclusion] The experiment laid basis for the exploration of the physical and ecological mechanism of underground plants adaptability to highland environment,their response to global climate changes and adjustment to high altitude ecological system. 展开更多
关键词 Quercus aquifolioides Total nitrogen non-structural Carbohydrates ELEVATION
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Hybrid particle filtering algorithm for GPS multipath mitigation 被引量:2
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作者 郑南山 蔡良师 +1 位作者 卞和方 林聪 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第5期1554-1561,共8页
An altemative algorithm for mitigating GPS multipath was presented by integrating unscented Kalman filter (UKF) and wavelet transform with particle filter. Within consideration of particle degeneracy, UKF was taken ... An altemative algorithm for mitigating GPS multipath was presented by integrating unscented Kalman filter (UKF) and wavelet transform with particle filter. Within consideration of particle degeneracy, UKF was taken for drawing particle. To remove the noise from raw data and data processing error, adaptive wavelet filtering with threshold was adopted while data preprocessing and drawing particle. Three algorithms, named EKF-PF, UKF-PF and WM-UKF-PF, were performed for comparison. The proposed WM-UKF-PF algorithm gives better error minimization, and significantly improves performance of multipath mitigation in terms of SNR and coefficient even though it has computation complexity. It is of significance for high-accuracy positioning and non-stationary deformation analysis. 展开更多
关键词 particle filtering wavelet transformation global positioning system (GPS) multipath mitigation
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