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Cascading failure modeling and survivability analysis of weak-communication underwater unmanned swarm networks
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作者 Yifan Yuan Xiaohong Shen +3 位作者 Lin Sun Ke He Yongsheng Yan Haiyan Wang 《Defence Technology(防务技术)》 2026年第2期66-82,共17页
Cascading failures pose a serious threat to the survivability of underwater unmanned swarm networks(UUSNs),significantly limiting their service ability in collaborative missions such as military reconnaissance and env... Cascading failures pose a serious threat to the survivability of underwater unmanned swarm networks(UUSNs),significantly limiting their service ability in collaborative missions such as military reconnaissance and environmental monitoring.Existing failure models primarily focus on power grids and traffic systems,and don't address the unique challenges of weak-communication UUSNs.In UUSNs,cascading failure present a complex and dynamic process driven by the coupling of unstable acoustic channels,passive node drift,adversarial attacks,and network heterogeneity.To address these challenges,a directed weighted graph model of UUSNs is first developed,in which node positions are updated according to ocean-current-driven drift and link weights reflect the probability of successful acoustic transmission.Building on this UUSNs graph model,a cascading failure model is proposed that integrates a normal-failure-recovery state-cycle mechanism,multiple attack strategies,and routingbased load redistribution.Finally,under a five-level connectivity UUSNs scheme,simulations are conducted to analyze how dynamic topology,network load,node recovery delay,and attack modes jointly affect network survivability.The main findings are:(1)moderate node drift can improve survivability by activating weak links;(2)based-energy routing(BER)outperform based-depth routing(BDR)in harsh conditions;(3)node self-recovery time is critical to network survivability;(4)traditional degree-based critical node metrics are inadequate for weak-communication UUSNs.These results provide a theoretical foundation for designing robust survivability mechanisms in weak-communication UUSNs. 展开更多
关键词 Weak communication Underwater unmanned swarm networks(UUSNs) Link success probability Cascading failure Node self-recovery Survivability analysis
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Transmission patterns of progressive damage and reliability analysis of reservoir-induced landslides considering local tensile failure
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作者 Minghao Miao Huiming Tang +5 位作者 Yinlong Jiang Kun Fang Changdong Li Cheng He Peng Cao Sha Lu 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期913-931,共19页
Reservoir-induced landslides in China's Three Gorges Reservoir area are prone to tensile cracks due to the influenceof their own weight and fluctuationsin water levels.The presence of cracks indicates that the ten... Reservoir-induced landslides in China's Three Gorges Reservoir area are prone to tensile cracks due to the influenceof their own weight and fluctuationsin water levels.The presence of cracks indicates that the tensile stress in the area has exceeded the tensile strength of the soil,leading to local instability.To explore the impact of tensile failure behavior on the stability and failure modes of reservoir landslides,the Huangtupo Riverside Slump#1 is taken as a case study.By considering local tensile failure,potential tensile cracks are incorporated into the analysis via the limit equilibrium method and reliability theory.The reliability of landslides under different tensile failure scenarios is quantified.Strain-softening characteristics of the soil are combined to further analyze the failure transmission path of the landslide.Finally,these potential failure modes were validated through physical model tests.The results show that cracks developing at rear positions reduce the stability of the slope and increase the probability of instability.During the destruction process,retrogressive failures with multiple sliding surfaces are likely to occur.However,tensile failure at the forefront reduces the likelihood of an individual slide mass descending.Progressive failure results in both regular and skip transmission patterns.Additionally,cracks and water level changes can also lead to shifts in the positions of the most dangerous blocks.Therefore,in practical landslide analysis and prevention,it is necessary to consider local tensile damage and identify potential tensile crack locations in advance to optimize prevention measures and accurately evaluate landslide risk. 展开更多
关键词 Reliability analysis Tensile failure Reservoir landslide Progressive damage failure mode Tensile crack
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Utility of the Vulnerable Elders Survey-13(VES-13) in detecting frailty and predicting prognosis in heart failure outpatients
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作者 Thaïs Roig Elisabet Zamora +15 位作者 Josep Lupón Beatriz González Ana Pulido Eva Crespo Patricia Velayos Carmen Rivas Violeta Díaz Yolanda López Andrea Borrellas Mar Domingo María Ruiz Pau Codina Evelyn Santiago-Vacas MiquelÀMas Ramón Miralles Antoni Bayes-Genis 《Journal of Geriatric Cardiology》 2026年第1期17-26,共10页
Background Frailty is common and significantly impacts prognosis in heart failure(HF). The Vulnerable Elders Survey-13(VES-13), widely used in oncogeriatrics and public health, remains unexplored as a frailty screenin... Background Frailty is common and significantly impacts prognosis in heart failure(HF). The Vulnerable Elders Survey-13(VES-13), widely used in oncogeriatrics and public health, remains unexplored as a frailty screening tool in HF outpatients. In this study, we prospectively evaluated VES-13 against a multimodal screening assessment in detecting frailty and predicting individual risk of adverse prognosis.Methods Frailty was assessed at the initial visit using both a multimodal approach, incorporating Barthel Index, Older American Resources and Services scale, Pfeiffer Test, abbreviated Geriatric Depression Scale, age > 85 years, lacking support systems,and VES-13. Patients scoring ≥ 3 on VES-13 or meeting at least one multimodal criterion were classified as frail. Endpoints included all-cause mortality, a composite of death or HF hospitalization, and recurrent HF hospitalizations.Results A total of 301 patients were evaluated. VES-13 identified 40.2% as frail and the multimodal assessment 33.2%. In Cox regression analyses, frailty identified by VES-13 showed greater prognostic significance than the multimodal assessment for allcause mortality(HR = 3.70 [2.15–6.33], P < 0.001 vs. 2.40 [1.46–4.0], P = 0.001) and the composite endpoint(HR = 3.13 [2.02–4.84], P< 0.001 vs. 1.96 [1.28–2.99], P = 0.002). Recurrent HF hospitalizations were four times more frequent in VES-13 frail patients while two times in those identified as frail by the multimodal assessment. Additionally, stratifying patients by VES-13 tertiles provided robust risk differentiation.Conclusions VES-13, a simple frailty tool, outperformed a comprehensive multimodal assessment and could be easily integrated into routine HF care, highlighting its clinical utility in identifying patients at risk for poor outcomes. 展开更多
关键词 barthel i FRAILTY heart failure hf Heart failure multimodal screening assessment multimodal approach detecting frailty Vulnerable Elders Survey
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Decade of insights on causes of scleral buckle failure in retinal detachment
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作者 Hu Cheng Liu Yin +6 位作者 Du Fan Zhu Li Xiang Nian Huang Zhijian Yan Ying Zeng Bo Chen Xiao 《国际眼科杂志》 2026年第2期197-201,共5页
AIM:To investigate the underlying causes of surgical failure and reoperation management in patients with rhegmatogenous retinal detachment(RRD)who underwent scleral buckle surgery at our institution.METHODS:This was a... AIM:To investigate the underlying causes of surgical failure and reoperation management in patients with rhegmatogenous retinal detachment(RRD)who underwent scleral buckle surgery at our institution.METHODS:This was a single-center,retrospective,descriptive study.The clinical data of 368 patients(387 eyes)with RRD who underwent scleral buckling(SB)surgery between August 2013 and July 2023 at our institution were collected.The aim was to analyze the causes of recurrence and the rationale for selecting reoperation methods.RESULTS:Totally 368 patients(387 eyes)were included in the analysis,comprising 222 males and 146 females.The average age was 30.26±14.18 years,and the mean follow-up duration was(48.33±20.39)mo.The success rate of SB surgery was 90.2%.Recurrent retinal detachment occurred in 38 eyes.Based on surgical records,the causes of SB failure were analyzed.The recurrence causes included abnormal compression ridge position(position,height,or width)in 14 eyes(36.8%,14/38),hole omission in 11 eyes(29.0%,11/38),proliferative vitreoretinopathy(PVR)in 10 eyes(26.3%,10/38),and new holes in 3 eyes(7.9%,3/38).Among these,8 eyes(21.1%,8/38)underwent repeat SB surgery,while the remaining 30 eyes(78.9%,30/38)underwent pars plana vitrectomy(PPV).Regarding tamponade agents,silicone oil was used in 11 eyes(36.7%,11/30),C_(3)F_(8) gas in 12 eyes(40.0%,12/30),and sterile air in 7 eyes(23.3%,7/30).CONCLUSION:SB surgery demonstrates a high success rate in the treatment of RRD.However,abnormal compression ridge position,missed holes during surgery,and PVR are the primary causes of SB failure.After addressing the reasons for failure,re-SB surgery or PPV can be effective alternatives. 展开更多
关键词 retinal detachment scleral buckling cause of failure REOPERATION
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Preterm heart failure and refractory lactic acidosis caused by congenital hypothyroidism:A case report and review of literature
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作者 Hong-Ju Chen Jiao Li +3 位作者 Xiao-Ming Xu Bo Zhang Bo-Chao Cheng Jing Shi 《World Journal of Clinical Cases》 2026年第1期43-51,共9页
BACKGROUND Congenital hypothyroidism(CH)is a common condition in both preterm and term infants characterized by either thyroid gland absence or hypofunctionality.The clinical association of refractory lactic acidosis ... BACKGROUND Congenital hypothyroidism(CH)is a common condition in both preterm and term infants characterized by either thyroid gland absence or hypofunctionality.The clinical association of refractory lactic acidosis and heart failure has rarely been observed in cases of pediatric patients with CH pathology.Here,we explored the etiological relationship between CH,heart failure,and refractory lactic acidosis to reflect the importance of thyroid function screening in neonates with heart disease.CASE SUMMARY A 33-day-old extremely premature female infant presented with tachypnea,respiratory distress,recurrent infections,and abdominal distension postnatal.On admission to our facility,she had cardiomegaly,hepatomegaly,and lactic acidosis(revealed on blood gas analysis),with lactate progressively rising to 25 mmol/L.Chest radiographs showed pulmonary congestion,while echocardiography revealed cardiac enlargement,left ventricular wall thickening,and pericardial effusion.Initial management aimed at correcting acidosis and treating heart failure proved ineffective.After reassessment,thyroid function tests showed significantly decreased triiodothyronine,free triiodothyronine,thyroxine,and free thyroxine levels,with a significantly increased thyroidstimulating hormone level,confirming a CH diagnosis.Levothyroxine was administered,resulting in rapid correction of lactic acidosis and gradual improvement of thyroid function and systemic symptoms,culminating in full recovery and discharge.We also reviewed the relevant literature on thyroid and cardiac dysfunctions in order to explore their deeper association.CONCLUSION This case links CH-induced heart failure with refractory lactic acidosis,urging prompt thyroid screening in affected neonates to reduce mortality. 展开更多
关键词 Congenital hypothyroidism Lactic acidosis Heart failure NEONATE PRETERM Case report
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Incidence of readmission,mortality,and quality of life in patients with heart failure:a comprehensive assessment at a tertiary care hospital in India
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作者 Mahesh Bhupal Chendake Abhijeet Bhausaheb Shelke Vaishali Rajsinh Mohite 《Frontiers of Nursing》 2026年第1期121-129,共9页
Objective:Heart failure(HF)is a complex clinical syndrome that affects nearly 64 million individuals globally.Frequent hospital readmissions lead to poor health outcomes,impact quality of life(QoL),and are associated ... Objective:Heart failure(HF)is a complex clinical syndrome that affects nearly 64 million individuals globally.Frequent hospital readmissions lead to poor health outcomes,impact quality of life(QoL),and are associated with high mortality rates.This study assessed readmissions,mortality,and QoL outcomes in patients with HF in a tertiary care hospital setting.Methods:Patients aged≥18 years with HF,who visited the tertiary care hospital in Karad,India were included in the study(November2019 to October 2021).Demographics,disease characteristics,and condition at discharge were recorded using the medical records of patients.The quantitative data included readmission rates and mortality rates.The qualitative aspects describing patients'QoL were assessed using a patient-reported 21-question QoL questionnaire.Results:A total of 98 patients,predominantly male(63.3%),with a mean age of 62.9 years were included.The majority of the patients(80.6%)required<15 days of hospitalization.The 2-year readmission rate was 24.4%,while the mortality rate was 43.9%.Self-care pattern showed that patients seemed to be taking mild to average care while taking good care was rare.The QoL data showed that 22.4% were living a good quality life,44.9% average,while 32.7% were living a low-quality life.Better education and better self-care were associated with a low rate of readmission.Conclusions:We were able to assess the incidence of readmission,mortality,and QoL in patients with HF in a tertiary care hospital setting.The study showed that HF impacts patients'physical,emotional,and psychological wellbeing. 展开更多
关键词 heart failure MORTALITY quality of life READMISSION standard of living
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Effect of dynamic disturbance frequency on brittle failure of granite in deep excavation
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作者 Ben-Guo He Hanyi Liu +1 位作者 Xia-Ting Feng Hongyuan Fu 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1002-1015,共14页
Dynamic disturbances with various frequencies could trigger different failure modes of deep excavations.Superimposed on this static stress are dynamic disturbances due to various dynamic vibrations,e.g.excavation blas... Dynamic disturbances with various frequencies could trigger different failure modes of deep excavations.Superimposed on this static stress are dynamic disturbances due to various dynamic vibrations,e.g.excavation blasting,blasting,tunnel boring machine(TBM)vibration,rockburst wave,earthquakes.Specifically,these dynamic sources are characterized by a wide range of wave frequencies f,resulting in differences in failure modes.A series of true-triaxial compression tests were conducted on granite to simulate the excavation-induced stress path in three-dimensional(3D)stresses.Subsequently,a dynamic disturbance with various frequencies was applied to a cuboid specimen,to reveal the behavior associated with brittle failure.The dynamic disturbance with frequencies f of 5 Hz,10 Hz,and 40 Hz generates less disturbed energy components in the granite together with higher peak strength.However,dynamic disturbances with f of 20 Hz and 30 Hz resulted in a lower peak strength;the peak strength of the rock increases sp albeit it decreases at first,then increases.This U-shaped phenomenon relates to the natural frequency of the granite under such stress conditions.Different rock lithologies consisting of diverse mineral composition,respond differently to each sensitive resonance frequency.Interestingly,the weak disturbance stress with a high frequency f and low amplitude A increases the ratio of crack damage to peak strength(scd/sp)in the granite.This leads to the inhibition of the expansion of the granite during the dynamic disturbance process.Multiple penetrating tensileeshear cracks appear in the s3-direction as the disturbance frequency f increases. 展开更多
关键词 True-triaxial compression Disturbance frequency Brittle failure Characteristic strength Deep excavation
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Mitochondrial dysfunction: a new target for traditional Chinese medicine in the treatment of chronic heart failure
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作者 Fuyun Jia Yadong Wang +8 位作者 Shengwei Gao Rui Zhang Shichuan Chen Hui Zhang Yinan Ma Zhengwei Zhang Junchi Guo Xi Zhang Qiang Xu 《Chinese Journal of Natural Medicines》 2026年第3期289-299,共11页
Chronic heart failure(CHF) remains a global health challenge with limited therapeutic options. Mitochondrial dysfunction is a key pathological feature, and traditional Chinese medicine(TCM) shows unique potential in t... Chronic heart failure(CHF) remains a global health challenge with limited therapeutic options. Mitochondrial dysfunction is a key pathological feature, and traditional Chinese medicine(TCM) shows unique potential in targeting this mechanism. Evidence from human and animal models of heart failure indicates that TCM can restore mitochondrial function by regulating mitochondrial Ca^(2+) homeostasis, oxidative stress, energy metabolism, mitochondrial dynamics, and mitophagy. TCM-based treatment of CHF offers notable clinical advantages, including improved therapeutic efficacy, enhanced cardiac function, and reduced incidence of major cardiovascular events. Experimental studies demonstrate that TCM decoctions and monomers modulate signaling pathways such as PPAR–RXRα, NF-κB, and PI3K/AKT to alleviate oxidative stress. TCM also increases AMPK activity via phosphorylation of PGC-1α, indirectly promoting mitochondrial biogenesis;attenuates calcium influx and enhances Ca^(2+) reuptake, thereby ameliorating myocardial mitochondrial dysfunction in CHF;and improves CHF by rebalancing mitochondrial dynamics and autophagy. 展开更多
关键词 Mitochondrial dysfunction Traditional Chinese medicine Chronic heart failure
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Experimental study on damage evolution and failure precursor characteristics of granite under thermal shock cycles
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作者 Zhenjiang Huang Mingxuan Shen +5 位作者 Yu Zhao Chaolin Wang Jing Bi Yongfa Zhang Shuang Dang Yuhang Zhao 《International Journal of Mining Science and Technology》 2026年第1期125-148,共24页
Investigating the damage evolution of surrounding rock under thermal shock cycles is crucial for ensuring the stability of engineering rock masses.This study performed Brazilian splitting tests on granite specimens un... Investigating the damage evolution of surrounding rock under thermal shock cycles is crucial for ensuring the stability of engineering rock masses.This study performed Brazilian splitting tests on granite specimens under varying temperature and cycle conditions,employing acoustic emission monitoring,digital image correlation,and three-dimensional scanning technology.A systematic analysis was conducted on the patterns of damage evolution,failure precursor,and response mechanisms under combined thermal and cyclic loading.Experimental results show that both P-wave velocity and tensile strength degrade significantly with increasing temperature and cycle count,with temperature having a more pronounced effect than cycle count.Notably,damage evolution exhibits a dual-threshold behavior in which degradation accelerates markedly above 400℃ and stabilizes after 5 thermal cycles.Fracture surfaces evolve from initially planar to rugged morphologies,with peak-valley height differences at 600℃ being approximately three times greater than those at 200℃.Furthermore,based on acoustic emission energy entropy analysis,we introduce a novel failure precursor indicator where the sustained increase and critical surge in average entropy serve as reliable early-warning signals for impending rock failure.These findings establish a solid theoretical basis and practical methodology for damage assessment and instability early-warning systems in high-temperature rock engineering. 展开更多
关键词 GRANITE Thermal shock cycles Acoustic emission Thermal damage failure precursor
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Joint beamforming design for low probability of intercept in transmit subaperturing MIMO radar
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作者 WU Jiale SHI Chenguang +1 位作者 WU Zhifeng ZHOU Jianjiang 《Journal of Systems Engineering and Electronics》 2026年第1期94-103,共10页
In this paper,the joint design of transmit and receive beamformers for transmit subaperturing multiple-input-multiple-output(TS-MIMO)radar is investigated,aiming to enhance its low probability of intercept(LPI)capabil... In this paper,the joint design of transmit and receive beamformers for transmit subaperturing multiple-input-multiple-output(TS-MIMO)radar is investigated,aiming to enhance its low probability of intercept(LPI)capability.The main objective is to simultaneously minimize the transmission power,suppress the transmit sidelobe levels,and minimize the probability of intercept,thus bolstering the LPI performance of the radar system while maintaining the desired target detection performance.An alternative optimization method is proposed to jointly optimize the transmit and receive beamformers,yielding an unified LPI optimization framework.Particularly,the proposed iterative algorithm based on the Lagrange duality theory for transmit beamforming is more efficient than the conventional convex optimization method.Numerical experiments highlight the effectiveness of the proposed approach in sidelobe suppression and computational efficiency. 展开更多
关键词 multiple-input-multiple-output(MIMO)radar BEAM-FORMING SUBARRAY low probability of intercept sidelobe suppression jamming
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Hot Drought Increased the Occurrence Probability of the 2025 Los Angeles Destructive Wildfires
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作者 Feng MA Xing YUAN Jason AOTKIN 《Advances in Atmospheric Sciences》 2026年第4期723-735,共13页
The western Los Angeles(LA)wildfires of early January 2025 caused catastrophic social and environmental impacts,drawing widespread attention.This study investigates the characteristics of these wildfires and quantifie... The western Los Angeles(LA)wildfires of early January 2025 caused catastrophic social and environmental impacts,drawing widespread attention.This study investigates the characteristics of these wildfires and quantifies the influence of heat and drought on their likelihood using a copula-based Bayesian probability framework.The wildfires were characterized by burned area(BA)and intensity(fire radiative power,FRP).The criteria establishing the presence of“hot drought”conditions were identified using the 5-day Standardized Temperature Index(STI)and 75-day Standardized Precipitation Index(SPI),respectively.The wildfire outbreak began on 7 January 2025 and burned for more than six days,with the total burned area exceeding 245 km^(2) and the cumulative FRP exceeding 41060 MW.Based on satellite-derived active fire observations from 2001 to 2025,we estimate that such large and intense wildfires during LA’s rainy season represent a once-in-a-67-year event.The wildfires were largely driven by the combination of hot and dry conditions,which dried out soils and vegetation that had proliferated due to above-average precipitation in previous winter seasons,thereby providing abundant fuel.Our seasonal analysis reveals that extreme drought increased the probability of wildfires matching the 2025 intensity and BA by 54%and 75%,respectively.Hot drought further amplified these probabilities by 149%(intensity)and 210%(BA).These findings suggest an elevated risk of large wildfires under hot drought conditions,contributing to their expansion into the non-traditional fire season. 展开更多
关键词 2025 western Los Angeles wildfires hot drought copula-based probability excessive vegetation growth Santa Ana winds
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Experimental and theoretical investigation of face failure and ground collapse during slurry pressure-balanced shield tunneling in saturated sand
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作者 Mengzhe Huo Weizhong Chen +3 位作者 Jingqiang Yuan Yunfa Li Yubiao Liu Qun Sui 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1320-1336,共17页
Shield tunneling in saturated ground poses challenges due to the potential risk of ground collapse resulting from seepage force and inadequate support pressure.This study employed a laboratory model test and a theoret... Shield tunneling in saturated ground poses challenges due to the potential risk of ground collapse resulting from seepage force and inadequate support pressure.This study employed a laboratory model test and a theoretical validation to elucidate the mechanisms of face failure and subsequent ground collapse in saturated ground during slurry pressure-balanced shield(SPBS)tunneling operations.A slurry circulation system was developed to ensure steady shield tunneling and to replicate the phenomena of ground collapse.Investigations into shield tunneling parameters and ground responses,including soil pressure,pore water pressure,and surface subsidence,were conducted to understand the mechanisms of face failure and subsequent ground collapse.The theoretical solution for the critical collapse pressure of the tunnel face,based on the rotational failure mechanism,was validated through the comparison with the experimentally determined critical collapse pressure.The results indicate that:(1)appropriate adjustments of tunneling parameters are crucial for promoting filtercake formation,maintaining chamber pressure,and minimizing ground subsidence;(2)chamber pressure,soil pressure,pore water pressure,and ground subsidence are closely correlated with shield tunneling parameters and the formation of filter cake;(3)ground collapse follows a continuous failure mode due to the destruction of filtercake and the decrease in chamber pressure;(4)the soil pressure at the cutterhead is more sensitive to disturbances from shield tunneling than chamber pressure;and(5)experimentally determined critical collapse pressures is consistent with the theoretical solution of limit analysis. 展开更多
关键词 Slurry shield model test Saturated sand Ground collapse Tunnel face stability Rotational failure mechanism
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Energy absorption properties and failure modes of flexible UHMWPE foam protective sandwich structure subjected to low-velocity impact
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作者 Xiaoke Liu Kejing Yu Pengwan Chen 《Defence Technology(防务技术)》 2026年第2期32-48,共17页
Flexible materials play a crucial role in protecting against behind armour blunt trauma(BABT).However,their compliance complicates the understanding of failure mechanisms and energy absorption.This study used a combin... Flexible materials play a crucial role in protecting against behind armour blunt trauma(BABT).However,their compliance complicates the understanding of failure mechanisms and energy absorption.This study used a combined experimental and numerical approach to investigate the response and failure modes of a flexible ultra-high-molecular-weight polyethylene(UHMWPE)foam protective sandwich structure(UFPSS)under low-velocity impact(LVI).A finite element(FE)model,accounting for nonlinear large deformation and strain-rate-dependent material behavior,was developed for a woven-UFPSS(featuring a plain-woven fabric structure)subjected to a 50 J impact.Experimental and numerical results showed strong agreement in peak force(error<5%),maximum displacement(error<6%),and buffer time(error<8%).The impact's kinetic energy was mainly converted into internal energy of the fabric and foam materials(~50%),viscous dissipation in the foam core(12%-15%),frictional work at the contact interfaces(5%-6%),and work by the pneumatic fixture clamping force(~38%).This study provides the first investigation of the LVI performance of sandwich structures with all soft material layers,offering significant insights for the application of compliant materials in protective fields. 展开更多
关键词 Sandwich structure Ultra-high-molecular-weight polyethylene(UHMWPE) Low-velocity impact(LVI) failure mode Energy absorption
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Influenceof native pores on the size distribution and predictability of rock failure
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作者 Lichang Wang Qi Hao +4 位作者 Yuchen Zhong Xiling Liu Qin Xie Xiaoran Tian Feifei Qin 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1447-1459,共13页
This study examines how native pore structures and loading conditions influencethe fracture size distribution and the predictability of catastrophic failure in rocks.Four lithologies with distinct pore characteristics... This study examines how native pore structures and loading conditions influencethe fracture size distribution and the predictability of catastrophic failure in rocks.Four lithologies with distinct pore characteristics,i.e.granite,limestone,red sandstone,and marble,were tested under uniaxial compression and Brazilian splitting.Nuclear magnetic resonance(NMR)was used to characterize pore structures,while acoustic emission(AE)monitoring captured the temporal evolution of microcracking.The relationships among pore properties,AE b-values,and failure predictability were systematically evaluated.Results show that the overall b-value is primarily controlled by native pore size rather than loading condition.Rocks with larger pores display higher b-value and greater temporal variability,whereas those with smaller pores exhibit lower and more stable b-value.To assess failure predictability,the AE count rate was incorporated into an inverse power law model.The model demonstrates higher predictive accuracy for high-porosity rocks.The average predicted failure time(t_(p))decreases monotonically with porosity:under uniaxial compression,t_(p)for granite,marble,limestone,and sandstone are 2.32,1.82,1.42,and 0.03,respectively;under Brazilian splitting,3.54,3.30,0.10,and 0.03.Among the four rock types,sandstone with the highest porosity exhibits the smallest discrepancy between predicted and actual failure time,whereas granite with the lowest porosity shows the largest.As porosity decreases,prediction accuracy progressively declines for limestone and marble.Overall,the findings indicate that native pore heterogeneity governs both fracture scaling behavior and failure predictability,and that these effects are largely independent of the loading conditions examined in this study. 展开更多
关键词 Rock deformation test Acoustic emission(AE) B-VALUE Inverse power law model Predictability of catastrophic failure
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Successful rescue activation of unfertilized oocytes with calcium ionophore(A23187)in a case of recurrent ICSI fertilization failure:A case report
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作者 Akash More Vilas Chimurkar +2 位作者 Namrata Choudhary Dipali More Sanket Mahajan 《Asian pacific Journal of Reproduction》 2026年第1期45-48,共4页
Rationale:This case report describes a couple with recurrent fertilization failure despite undergoing multiple cycles of intracytoplasmic sperm injection(ICSI).The principal clinical concern was suspected oocyte activ... Rationale:This case report describes a couple with recurrent fertilization failure despite undergoing multiple cycles of intracytoplasmic sperm injection(ICSI).The principal clinical concern was suspected oocyte activation deficiency(OAD),in which fertilization is impeded due to the oocyte’s inability to initiate embryogenesis,commonly attributed to inadequate intracellular calcium(Ca^(2+))release following sperm injection.Patient concerns:The couple repeatedly experienced complete or near-complete fertilization failure in previous ICSI cycles,raising suspicion of an underlying oocyte activation defect.Diagnosis:Based on the repeated absence of fertilization post-ICSI and clinical history,a diagnosis of suspected OAD leading to recurrent ICSI fertilization failure was considered.Interventions:Artificial oocyte activation(AOA)using the calcium ionophore A23187 was performed.After ICSI,unfertilized oocytes were exposed to the ionophore to induce Ca^(2+)influx,simulating physiological calcium oscillations essential for oocyte activation.The efficacy of intervention was evaluated through subsequent embryonic development,morphological grading,and chromosomal integrity.Outcomes:Following AOA treatment,successful oocyte activation occurred,resulting in the formation of high-grade embryos with normal developmental progression.Chromosomal analysis revealed no detectable abnormalities,indicating genomic stability.Lessons:Calcium ionophore–mediated AOA may serve as an effective adjunct in cases of recurrent ICSI failure attributed to OAD.This case highlights the importance of individualized therapeutic strategies in assisted reproduction;however,further research is needed to refine protocols,validate broader clinical efficacy,and assess long-term safety,including potential epigenetic risks. 展开更多
关键词 Oocyte activation deficiency Intracytoplasmic sperm injection Artificial oocyte activation Calcium ionophore A23187 Fertilization failure Assisted reproductive technology
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Failure probability assessment of step-like landslide using a hybrid interval prediction method under uncertain conditions
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作者 Zhou Zheng Yanlong Li +3 位作者 Ye Zhang Lifeng Wen Ting Wang Xinjian Sun 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第11期7265-7287,共23页
To address prediction errors and limited information extraction in machine learning(ML)-based interval prediction,a hybrid model was proposed for interval estimation and failure assessment of step-like landslides unde... To address prediction errors and limited information extraction in machine learning(ML)-based interval prediction,a hybrid model was proposed for interval estimation and failure assessment of step-like landslides under uncertainty.The model decomposed displacements into trend and periodic components via Variational Mode Decomposition(VMD)and K-shape clustering.The Residual and Moving Block Bootstrap methods were used to generate pseudo datasets.Polynomial regressionwas adopted for trend forecasting,whereas the Dense Convolutional Network(DenseNet)and Long Short-Term Memory(LSTM)networks were employed for periodic displacement prediction.An Extreme Learning Machine(ELM)was used to estimate the noise variance,enabling the construction of Prediction Intervals(PIs)and quantificationof displacement uncertainty.Failure probabilities(Pf)were derived from PIs using an improved tangential angle criterion and reliability analysis.The model was validated on three step-like landslides in the Three Gorges Reservoir Area,achieving stability assessment accuracies of 99.88%(XD01),99.93%(ZG93),99.89%(ZG118),and 100%for ZG110 and ZG111 across the Baishuihe and Bazimen landslides.For the Shuping landslide,the predictions aligned with fieldobservations before and after the 2014–2015 remediation,with P_(f)remaining near zero post-2015 except for occasional peaks.The model outperformed conventional ML approaches by yielding narrower PIs.At XD01 with 90%PI nominal confidencelevel(PINC),the coverage width-based criterion(CWC)and PI average width(PIAW)were 3.38 mm.The mean values of the PIs exhibited high accuracy,with a Mean Absolute Error(MAE)of 0.28 mm and Root Mean Square Error(RMSE)of 0.39 mm.These results demonstrate the robustness of the proposed model in improving landslide risk assessment and decision-making under uncertainty. 展开更多
关键词 Step-like landslides failure probability Prediction intervals Deep learning Epistemic uncertainties
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Acute liver failure caused by amino acid or organic acid related inborn errors of metabolism
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作者 Ying Zhou Chi Chen Xin Yang 《Hepatobiliary & Pancreatic Diseases International》 2026年第1期112-114,共3页
Inborn errors of metabolism(IEMs)are a large group of disorders resulting from deficient activities in several metabolic pathways due to the dysfunction of a distinct enzyme associated with a biochemical pathway[1,2].... Inborn errors of metabolism(IEMs)are a large group of disorders resulting from deficient activities in several metabolic pathways due to the dysfunction of a distinct enzyme associated with a biochemical pathway[1,2].Toxic intermediates will be produced due to the dysfunction of biochemical pathways.The liver is responsible for many essential metabolic processes,therefore it becomes one of the most severely affected organ by metabolic diseases[3].Early onset of liver disorders in IEMs includes jaundice,hepatomegaly,splenomegaly,ascites,hepatic encephalopathy,and liver failure[4].In infants and young children under 3 years old with acute liver failure(ALF),IEMs account for 18.9%-43%[5]. 展开更多
关键词 biochemical pathway toxic intermediates metabolic diseases early acute liver failure inborn errors metabolism iems organic acid dysfunction distinct enzyme metabolic processestherefore metabolic pathways
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A New Approach for the Calculation of Slope Failure Probability with Fuzzy Limit-State Functions
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作者 Jianing Hao Dan Yang +2 位作者 Guanxiong Ren Ying Zhao Rangling Cao 《Fluid Dynamics & Materials Processing》 2025年第1期141-159,共19页
This study presents an innovative approach to calculating the failure probability of slopes by incorporating fuzzylimit-state functions,a method that significantly enhances the accuracy and efficiency of slope stabili... This study presents an innovative approach to calculating the failure probability of slopes by incorporating fuzzylimit-state functions,a method that significantly enhances the accuracy and efficiency of slope stability analysis.Unlike traditional probabilistic techniques,this approach utilizes a least squares support vector machine(LSSVM)optimized with a grey wolf optimizer(GWO)and K-fold cross-validation(CV)to approximate the limit-statefunction,thus reducing computational complexity.The novelty of this work lies in its application to one-dimensional(1D),two-dimensional(2D),and three-dimensional(3D)slope models,demonstrating its versatility andhigh precision.The proposed method consistently achieves error margins within 3%of Monte Carlo simulation(MCS)results,while substantially reducing computation time,particularly for 2D and 3D models.This makes theapproach highly practical for real-world engineering applications.Furthermore,by applying fuzzy mathematics tohandle uncertainties in geotechnical properties,the method offers a more realistic and comprehensive understandingof slope stability.As water is the main factor influencing the stability of slopes,this aspect is investigatedby calculating the phreatic line after the change in water level.Relevant examples are used to show that the failureprobability of a slope under water wading condition can increase by more than 20%(increase rates in 1D,2D and3D conditions being 25%,27%and 31%,respectively)compared with the natural condition.The influence ofdiverse fuzzy membership functions—linear,normal,and Cauchy—on failure probability is also considered.Thisresearch not only provides a strategy for better calculation of the slope failure probability but also pioneers theintegration of computational intelligence,fuzzy logic and fluid-dynamics in geotechnical engineering,presentingan innovative and efficient tool for slope stability analysis. 展开更多
关键词 Least Squares Support Vector Machine(LSSVM) Grey Wolf Optimizer(GWO) slope stability analysis fuzzy set theory failure probability estimation
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AN IMPROVED FOSM METHOD FOR CALCULATING FAILURE PROBABILITY OF WELDED PIPES WITH FLAWS 被引量:1
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作者 刘敏 霍立兴 张玉凤 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1999年第2期188-192,共5页
The R F first order second moment method will produce more error for calculating the reliability of welded engineering pipe structures when the failure function is seriously nonlinear and the random variables don... The R F first order second moment method will produce more error for calculating the reliability of welded engineering pipe structures when the failure function is seriously nonlinear and the random variables don′t serve as normal distribution. In order to increase the computing accuracy of reliability, an improved FOSM method is used for calculating the failure probability of welded pipes with flaws in this paper. Because of solving the problems of the linear expansion of failure function at the failure point and constructing equivalent normal variables, the new algorithm can greatly improve the calculating accuracy of probability of the welded pipes with cracks. The examples show that this method is simple, efficient and accurate for reliability safety assessment of the welded pipes with cracks. It can save more time than the Monte Carlo method does, so that the improved FOSM method is recommended for engineering reliability safety assessment of the welded pipes with flaws. 展开更多
关键词 welded structure failure probability FLAWS PIPES first order second moment
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Evaluation of the effect of geometrical parameters on stope probability of failure in the open stoping method using numerical modeling 被引量:17
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作者 Shahriyar Heidarzadeh Ali Saeidi Alain Rouleau 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2019年第3期399-408,共10页
Stress-induced failure is among the most common causes of instability in Canadian deep underground mines.Open stoping is the most widely practiced underground excavation method in these mines,and creates large stopes ... Stress-induced failure is among the most common causes of instability in Canadian deep underground mines.Open stoping is the most widely practiced underground excavation method in these mines,and creates large stopes which are subjected to stress-induced failure.The probability of failure(POF)depends on many factors,of which the geometry of an open stope is especially important.In this study,a methodology is proposed to assess the effect of stope geometrical parameters on the POF,using numerical modelling.Different ranges for each input parameter are defined according to previous surveys on open stope geometry in a number of Canadian underground mines.A Monte-Carlo simulation technique is combined with the finite difference code FLAC3D,to generate model realizations containing stopes with different geometrical features.The probability of failure(POF)for different categories of stope geometry,is calculated by considering two modes of failure;relaxation-related gravity driven(tensile)failure and rock mass brittle failure.The individual and interactive effects of stope geometrical parameters on the POF,are analyzed using a general multi-level factorial design.Finally,mathematical optimization techniques are employed to estimate the most stable stope conditions,by determining the optimal ranges for each stope’s geometrical parameter. 展开更多
关键词 STOPE stability STOPE GEOMETRICAL parameters probability of failure General FACTORIAL design Numerical modeling Sublevel OPEN STOPING
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