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
This paper investigates the reliability of internal marine combustion engines using an integrated approach that combines Fault Tree Analysis(FTA)and Bayesian Networks(BN).FTA provides a structured,top-down method for ...This paper investigates the reliability of internal marine combustion engines using an integrated approach that combines Fault Tree Analysis(FTA)and Bayesian Networks(BN).FTA provides a structured,top-down method for identifying critical failure modes and their root causes,while BN introduces flexibility in probabilistic reasoning,enabling dynamic updates based on new evidence.This dual methodology overcomes the limitations of static FTA models,offering a comprehensive framework for system reliability analysis.Critical failures,including External Leakage(ELU),Failure to Start(FTS),and Overheating(OHE),were identified as key risks.By incorporating redundancy into high-risk components such as pumps and batteries,the likelihood of these failures was significantly reduced.For instance,redundant pumps reduced the probability of ELU by 31.88%,while additional batteries decreased the occurrence of FTS by 36.45%.The results underscore the practical benefits of combining FTA and BN for enhancing system reliability,particularly in maritime applications where operational safety and efficiency are critical.This research provides valuable insights for maintenance planning and highlights the importance of redundancy in critical systems,especially as the industry transitions toward more autonomous vessels.展开更多
It is well recognized that Structural Health Monitoring(SHM)reliability evaluation is a key aspect that needs to be urgently addressed to promote the wide application of SHM methods.However,the existing studies typica...It is well recognized that Structural Health Monitoring(SHM)reliability evaluation is a key aspect that needs to be urgently addressed to promote the wide application of SHM methods.However,the existing studies typically transfer the Non-Destructive Testing/Evaluation(NDT/E)reliability metrics to SHM without a systematic analysis of where these metrics originated.Seldom attentions are paid to the evaluation conditions which are very important to apply these metrics.Aimed at this issue,a new condition control-based Dual-Reliability Evaluation(Dual-RE)method for SHM is proposed.This new method is proposed based on a systematic analysis of the whole framework of reliability evaluation from instrument to NDT,and emphasis is paid to the evaluation condition control.Based on these analyses,considering the special online application scenario of SHM,the proposed Dual-RE method contains two key components:Integrated Sensor-based SHM-RE(IS-SHM-RE)and Critical Service Condition-based SHM-RE(CSC-SHM-RE).ISSHM-RE evaluates the reliability of integrated SHM sensor and system themselves under approximate repeatability conditions,while CSC-SHM-RE assesses SHM reliability under the dominant uncertainties during service,namely intermediate conditions.To demonstrate the Dual-RE,crack monitoring by using the Guided Wave-based-SHM(GW-SHM)on aircraft lug structures is taken as a case study.Both the crack detection and sizing performance are evaluated from accuracy and uncertainty.展开更多
In this work,we demonstrated the InSnO(ITO)TFTs passivated with SiO_(2)via the PECVD process compatible with large-area production for the first time.The passivated ITO TFTs with various channel thicknesses(t_(ch)=4,5...In this work,we demonstrated the InSnO(ITO)TFTs passivated with SiO_(2)via the PECVD process compatible with large-area production for the first time.The passivated ITO TFTs with various channel thicknesses(t_(ch)=4,5,6 nm)exhibit excellent electrical performance and superior uniformity.The reliability properties of ITO TFTs were evaluated in detail under positive bias stress(PBS)conditions before and after passivation.Compared to the devices without passivation,the passivated devices have only 50%threshold voltage degradation(ΔV_(th))and 50%newly generated traps due to excellent isolation of the ambient atmosphere.The negligible performance degradation of ITO TFTs with passivation during negative bias stress(NBS)and negative bias temperature stress(NBTS)verifies the outstanding immunity to the water vapor of the SiO_(2)passivation layer.Overall,the ITO TFT with the t_(ch)of 6 nm and with SiO_(2)passivation exhibits the best performance in terms of electrical properties,uniformity,and reliability,which is promising in large-area production.展开更多
To study the durability of concrete in harsh environments in Northwest China,concrete was prepared with various durability-improving materials such as concrete anti-erosion inhibitor(SBT-TIA),acrylate polymer(AP),supe...To study the durability of concrete in harsh environments in Northwest China,concrete was prepared with various durability-improving materials such as concrete anti-erosion inhibitor(SBT-TIA),acrylate polymer(AP),super absorbent resin(SAP).The erosion mode and internal deterioration mechanism under salt freeze-thaw cycle and dry-wet cycle were explored.The results show that the addition of enhancing materials can effectively improve the resistance of concrete to salt freezing and sulfate erosion:the relevant indexes of concrete added with X-AP and T-AP are improved after salt freeze-thaw cycles;concrete added with SBTTIA shows optimal sulfate corrosion resistance;and concrete added with AP displays the best resistance to salt freezing.Microanalysis shows that the increase in the number of cycles decreases the generation of internal hydration products and defects in concrete mixed with enhancing materials and improves the related indexes.Based on the Wiener model analysis,the reliability of concrete with different lithologies and enhancing materials is improved,which may provide a reference for the application of manufactured sand concrete and enhancing materials in Northwest China,especially for the study of the improvement effects and mechanism of enhancing materials on the performance of concrete.展开更多
In reliability analyses,the absence of a priori information on the most probable point of failure(MPP)may result in overlooking critical points,thereby leading to biased assessment outcomes.Moreover,second-order relia...In reliability analyses,the absence of a priori information on the most probable point of failure(MPP)may result in overlooking critical points,thereby leading to biased assessment outcomes.Moreover,second-order reliability methods exhibit limited accuracy in highly nonlinear scenarios.To overcome these challenges,a novel reliability analysis strategy based on a multimodal differential evolution algorithm and a hypersphere integration method is proposed.Initially,the penalty function method is employed to reformulate the MPP search problem as a conditionally constrained optimization task.Subsequently,a differential evolution algorithm incorporating a population delineation strategy is utilized to identify all MPPs.Finally,a paraboloid equation is constructed based on the curvature of the limit-state function at the MPPs,and the failure probability of the structure is calculated by using the hypersphere integration method.The localization effectiveness of the MPPs is compared through multiple numerical cases and two engineering examples,with accuracy comparisons of failure probabilities against the first-order reliability method(FORM)and the secondorder reliability method(SORM).The results indicate that the method effectively identifies existing MPPs and achieves higher solution precision.展开更多
Purpose–This paper focuses on studying the reliability allocation for the railway system,aiming to improve the overall reliability of the railway system and ensure safety operation.Design/methodology/approach–In vie...Purpose–This paper focuses on studying the reliability allocation for the railway system,aiming to improve the overall reliability of the railway system and ensure safety operation.Design/methodology/approach–In view of the complex structure of the railway system,involving many subsystems,this paper analyzes the close dynamic coupling effect between railway subsystems.Based on this,taking the railway system failure as the top event,a fault tree is constructed in this paper.Then,a reliability allocation method based on the fault tree is employed to allocate the reliability index.Finally,a numerical experiment is implemented to show the performance of the reliability allocation method.Findings–The results showed that each subsystem needs to improve its reliability to meet the specified railway system reliability requirements,and the traction power supply system is the most important subsystem,which is the most efficient in improving the reliability of the railway system.Originality/value–For the first time,starting from a holistic perspective of the system,reliability allocation is carried out based on the importance of each railway subsystem.展开更多
Autonomous Underwater Vehicles(AUVs)are pivotal for deep-sea exploration and resource exploitation,yet their reliability in extreme underwater environments remains a critical barrier to widespread deployment.Through s...Autonomous Underwater Vehicles(AUVs)are pivotal for deep-sea exploration and resource exploitation,yet their reliability in extreme underwater environments remains a critical barrier to widespread deployment.Through systematic analysis of 150 peer-reviewed studies employing mixed-methods research,this review yields three principal advancements to the reliability analysis of AUVs.First,based on the hierarchical functional division of AUVs into six subsystems(propulsion system,navigation system,communication system,power system,environmental detection system,and emergency system),this study systematically identifies the primary failure modes and potential failure causes of each subsystem,providing theoretical support for fault diagnosis and reliability optimization.Subsequently,a comprehensive review of AUV reliability analysis methods is conducted from three perspectives:analytical methods,simulated methods,and surrogate model methods.The applicability and limitations of each method are critically analyzed to offer insights into their suitability for engineering applications.Finally,the study highlights key challenges and research hotpots in AUV reliability analysis,including reliability analysis under limited data,AI-driven reliability analysis,and human reliability analysis.Furthermore,the potential of multi-sensor data fusion,edge computing,and advanced materials in enhancing AUV environmental adaptability and reliability is explored.展开更多
Continuously increasing inflation is a major challenge in presenting reliable and relevant financial reports,especially in developing countries like Indonesia.This study aims to analyze the role of inflation accountin...Continuously increasing inflation is a major challenge in presenting reliable and relevant financial reports,especially in developing countries like Indonesia.This study aims to analyze the role of inflation accounting in increasing the reliability of financial reports during times of high inflation.With a qualitative-descriptive approach,this research examines two main methods in inflation accounting,namely General Price Level Accounting(GPLA)and Current Cost Accounting(CCA),and their impact on the value of assets,liabilities,income,and costs.The analysis results show that historical cost-based financial reports do not reflect actual economic conditions during inflation,so they can be misleading in decision making.The application of inflation accounting,through adjustments to purchasing power and current prices,has been proven to be able to increase the relevance and reliability of financial information.However,limitations in implementation in Indonesia are due to the lack of regulations and practical understanding regarding this method.Therefore,the application of inflation accounting is important in supporting the quality of financial reports and more accurate decision making amidst economic instability.展开更多
The study aims to determine the validity and reliability of the Wechsler Preschool and Primary Scale of Intelligence–Third Edition(WPPSI-III)scores in a sample of kindergarten and lower primary pupils from Khartoum S...The study aims to determine the validity and reliability of the Wechsler Preschool and Primary Scale of Intelligence–Third Edition(WPPSI-III)scores in a sample of kindergarten and lower primary pupils from Khartoum State,Sudan.It also aims to examine whether test’s factor structure in this sample replicated that of the original WPPSI-III.The study sample consisted of 384 kindergarten and primary school children in Khartoum State(females=50%mean age=4.14,SD=1.37),selected using stratified random sampling across its seven localities:Khartoum,Jebel Awliya,Khartoum Bahri,East Nile,Omdurman,Ombada,Karari.For concurrent validation,the children additionally completed the Goodenough Draw-a-Man Test,and the Colored Progressive Matrices.WPPSI-III scores demonstrated high internal consistency across the subtest items.Confirmatory factor analysis indicators for total,verbal,and performance intelligence were all excellent.The scale also showed weak to strong score stability ranging from 0.25(weak)to 0.88(strong)based on the Spearman-Brown equation,0.25 to 0.75 based on the Guttman split-half method.The Cronbach’s alpha coefficient scores ranged from 0.54 to 0.93.The WPPSI-III and Goodenough Draw-a-Man Test scores concurrent validity scores were poor(0.05)to modest(0.31),and while those with the Colored Progressive Matrices test were poor(r=0.04–0.18).Thesefindings provide evidence to suggest that the WPPSI-III is appropriate for research use with kindergarten and lower primary school students in Khartoum State,Sudan.展开更多
Objective:This study aims to develop an assessment tool for postoperative wound healing in adult patients with benign anal canal and rectal diseases and to validate its reliability and validity.Methods:Based on Levine...Objective:This study aims to develop an assessment tool for postoperative wound healing in adult patients with benign anal canal and rectal diseases and to validate its reliability and validity.Methods:Based on Levine’s Conservation Model as the theoretical framework,an item pool was formed through literature review,and the initial draft of the scale was refined through two rounds of Delphi expert consultation.A total of 200 postoperative patients were selected for item analysis,internal consistency testing,content validity,and structural validity analysis.Results:The final tool comprises four dimensions:energy conservation,structural integrity,personal integrity,and social integrity,with a total of 24 items.It demonstrates good content validity(I-CVI 0.82-1.00,S-CVI/Ave 0.95,S-CVI/UA 0.87)and excellent internal consistency(Cronbach’sαfor the overall scale was 0.934).Exploratory factor analysis revealed a KMO value of 0.931,Bartlett’s test of sphericityχ^(2)=4147.853(p<0.001),and four common factors were extracted,accounting for a cumulative variance contribution rate of 64.345%,indicating ideal structural validity.Conclusion:The results indicate that the assessment tool has good reliability and validity and can systematically evaluate postoperative wound healing,providing a scientific basis for clinical individualized nursing interventions.展开更多
BACKGROUND During the gradual decline of physical and social functioning associated with end-stage renal disease,patients might experience a premonition of impending death,resulting in a series of pre-mourning grief r...BACKGROUND During the gradual decline of physical and social functioning associated with end-stage renal disease,patients might experience a premonition of impending death,resulting in a series of pre-mourning grief responses called preparatory grief.The preparatory grief in advanced cancer patients(PGAC)scale is the most widely used preparatory grief scale for patients on hemodialysis in China.AIM To verify the reliability and validity of the PGAC scale in patients on hemodialysis.METHODS In total,327 patients undergoing regular hemodialysis in the blood purification center of three grade-A tertiary hospitals in Guangdong and Guizhou provinces were selected by convenience sampling.The assessment was administered using the general information questionnaire and the Chinese version of PGAC.SPSS 25.0 and Amos 24.0 were used for item analysis,confirmatory factor analysis(CFA),convergent validity,and internal consistency reliability estimation.RESULTS In the modified Chinese version of PGAC,7 dimensions covering 27 total items were retained.CFA revealed a good fit of the factor model(chi-square degree of freedom=2.056,standardized root mean square residual=0.0479,root mean square error of approximation=0.0570,GFI=0.872,AGFI=0.841,IFI=0.931,CFI=0.930,TLI=0.919).The factor loadings of the items ranged 0.503-0.884.The composite reliability ranged 0.664-0.914,and the average variance extracted ranged 0.366-0.747.Cronbach’sαof the scale was 0.945,and Cronbach’sαfor various dimensions ranged 0.662-0.914.CONCLUSION The modified PGAC has good reliability and validity,and it can effectively measure preparatory grief in patients on hemodialysis.展开更多
Reliability analysis of soil slopes under rainfall is an important task for landslide risk assessment.Previous studies rarely contribute to the probabilistic analysis of slope stability under rainfall with reinforceme...Reliability analysis of soil slopes under rainfall is an important task for landslide risk assessment.Previous studies rarely contribute to the probabilistic analysis of slope stability under rainfall with reinforcement.A new method is suggested for reliability analysis of soil slopes stabilized with piles under rainfall.First,an efficient numerical model is exploited for slope stability analysis,where two types of slope failure modes,i.e.,plastic flow and local failure are considered.To address the blocking effect of piles during seepage analysis,the equivalent hydraulic conductivity of the pile area is estimated according to the effective medium theory.The stabilizing force of piles is investigated by an analytical approach.For saving computational effort,the response surface is established based on a multi-class classification model to predict two types of slope failure modes.Finally,uncertainties in soil parameters and rainfall events are both modelled,and the failure probability of soil slopes within a given time period is assessed through Monte Carlo simulation.An illustrative example is used to demonstrate the performance of the suggested method.It is found that the slope is mainly controlled by local failure.As the pile spacing increases,the likelihood of plastic flow significantly increases.As the piles are located near the slope crest,plastic flow is effectively prevented and the slope is better stabilized against rainfall.If rainfall uncertainties are not considered,the slope failure probability is significantly overestimated.Overall,this study can provide a useful guidance for the design of pile-stabilized slopes against rainfall infiltration.展开更多
BACKGROUND The Victorian institute of sports assessment for patellar tendons questionnaire(VISA-P),a valid tool for patellar tendinopathy,has been used for patellofemoral pain(PFP).AIM To validate VISA-P in PFP.METHOD...BACKGROUND The Victorian institute of sports assessment for patellar tendons questionnaire(VISA-P),a valid tool for patellar tendinopathy,has been used for patellofemoral pain(PFP).AIM To validate VISA-P in PFP.METHODS Study of validity,responsiveness and feasibility following COSMIN.Inclusion criteria:Subjects with PFP,aged 18 to 55.Agreement among 10 experts on the relevance and clarity of each item using Aiken's V coefficient determined content validity.An exploratory factorial analysis established structural validity.The correlation of VISA-P with knee injury and osteoarthritis outcome score for PFP and Osteoarthritis(KOOS-PF)and Kujala patellofemoral score(KPS;specific for PFP)analyzed the construct validity.Internal consistency was calculated with Cronbach'sαand test-retest reliability with the intraclass correlation coefficient(ICC).Feasibility considered the subjects'self-completion time.RESULTS The sample consisted of 103 knees from 73 subjects(47 female/26 male;aged 34.9±13 SD).The items were relevant and clear,with the exception of item-8,which didn't reach an acceptable level of agreement on clarity.Exploratory factorial analysis found a 2-factor solution,which explained 63.48%of the variance.VISAP achieved a strong and significant correlation with KOOS-PF(Spearman rho=0.826;P<0.001)and KPS(Spearman rho=0.771;P<0.001).The questionnaire showed adequate reliability(Cronbach'sα:0.752;ICC:0.934;P<0.0001;95%CI:0.902-0.955).The mean self-completion time was 232±0.52 SD seconds.CONCLUSION VISA-P proved to be valid and reliable to functionally assess PFP and/or chondromalacia patella.VISA-P is a feasible tool in the clinical and research environment,quick and easy to complete.展开更多
The dynamic avalanche effect is a critical factor influencing the performance and reliability of the field-stop insulated gate bipolar transistors(FS-IGBT).Unclamped inductive switching(UIS)is the primary method for t...The dynamic avalanche effect is a critical factor influencing the performance and reliability of the field-stop insulated gate bipolar transistors(FS-IGBT).Unclamped inductive switching(UIS)is the primary method for testing the dynamic avalanche capability of FS-IGBTs.Numerous studies have demonstrated that factors such as device structure,avalanche-generating current filaments,and electrical parameters influence the dynamic avalanche effect of the FS-IGBT.However,few studies have focused on enhancing the avalanche reliability of the FS-IGBT by adjusting circuit parameters during operation.In this paper,the dynamic avalanche effect of the FS-IGBT under UIS conditions is comprehensively investigated through a series of comparative experiments with varying circuit parameters,including bus voltage V_(DC),gate voltage V_(G),gate resistance R_(g),load inductance L,and temperature TC.Furthermore,a method to enhance the dynamic avalanche reliability of the FS-IGBT under UIS by optimizing circuit parameters is proposed.In practical applications,reducing gate voltage,increasing load inductance,and lowering temperature can effectively improve the dynamic avalanche capability of the FS-IGBT.展开更多
The beyond fifth-generation Internet of Things requires more capable channel coding schemes to achieve high-reliability,low-complexity and lowlatency communications.The theoretical analysis of error-correction perform...The beyond fifth-generation Internet of Things requires more capable channel coding schemes to achieve high-reliability,low-complexity and lowlatency communications.The theoretical analysis of error-correction performance of channel coding functions as a significant way of optimizing the transmission reliability and efficiency.In this paper,the efficient estimation methods of the block error rate(BLER)performance for rate-compatible polar codes(RCPC)are proposed under several scenarios.Firstly,the BLER performance of RCPC is generally evaluated in the additive white Gaussian noise channels.That is further extended into the Rayleigh fading channel case using an equivalent estimation method.Moreover,with respect to the powerful decoder such as successive cancellation list decoding,the performance estimation is derived analytically based on the polar weight spectrum and BLER upper bounds.Theoretical evaluation and numerical simulation results show that the estimated performance can fit well the practical simulated results of RCPC under the objective conditions,verifying the validity of our proposed performance estimation methods.Furthermore,the application designs of the reliability estimation of RCPC are explored,particularly in the advantages of the signal-to-noise(SNR)estimation and throughput efficiency optimization of polar coded hybrid automatic repeat request.展开更多
Nodal pricing is a critical mechanism in electricity markets,utilized to determine the cost of power transmission to various nodes within a distribution network.As power systems evolve to incorporate higher levels of ...Nodal pricing is a critical mechanism in electricity markets,utilized to determine the cost of power transmission to various nodes within a distribution network.As power systems evolve to incorporate higher levels of renewable energy and face increasing demand fluctuations,traditional nodal pricing models often fall short to meet these new challenges.This research introduces a novel enhanced nodal pricing mechanism for distribution networks,integrating advanced optimization techniques and hybrid models to overcome these limitations.The primary objective is to develop a model that not only improves pricing accuracy but also enhances operational efficiency and system reliability.This study leverages cutting-edge hybrid algorithms,combining elements of machine learning with conventional optimization methods,to achieve superior performance.Key findings demonstrate that the proposed hybrid nodal pricing model significantly reduces pricing errors and operational costs compared to conventional methods.Through extensive simulations and comparative analysis,the model exhibits enhanced performance under varying load conditions and increased levels of renewable energy integration.The results indicate a substantial improvement in pricing precision and network stability.This study contributes to the ongoing discourse on optimizing electricity market mechanisms and provides actionable insights for policymakers and utility operators.By addressing the complexities of modern power distribution systems,our research offers a robust solution that enhances the efficiency and reliability of power distribution networks,marking a significant advancement in the field.展开更多
Objective:This study aimed to translate the de Morton Mobility Index(DEMMI)into Thai and assess its measurement properties.Methods:The de Morton Mobility Index(DEMMI)was translated into Thai using a cross-cultural tra...Objective:This study aimed to translate the de Morton Mobility Index(DEMMI)into Thai and assess its measurement properties.Methods:The de Morton Mobility Index(DEMMI)was translated into Thai using a cross-cultural translation method.A cross-sectional study was conducted in four public hospitals in Thailand between January and March 2023.A total of 260 patients were recruited from outpatient clinics.Convergent and known-group validity were evaluated through hypothesis testing.Construct validity was examined using confirmatory factor analysis.Reliability was assessed using Cronbach’s a coefficient.We also employed the Rasch analysis to validate validity and person reliability.Results:Content validity was high(S-CVI=0.96,I-CVI range:0.80e1.00).Strong convergent validity was observed,with a significant correlation(r=0.761,P<0.001)between the Thai DEMMI and the Parker Mobility Scale(PMS).Known-group validity was evident,demonstrating differences in scores across various patient groups.A confirmatory factor analysis supported the hypothesized factor structure of the Thai DEMMI with good fit indices:χ^(2)(df=4)=5.101,P=0.2771;χ^(2)/df=1.275,RMSEA=0.033;CFI=0.998;TLI=0.995;SRMR=0.016.The Thai DEMMI exhibited high internal consistency(Cronbach’s a=0.88).Rasch analysis revealed good person reliability(0.91)and acceptable information-weighted fit means square statistic(0.73-1.06).However,most items showed good fit based on the outlier-sensitive fit means square statistics(Outfit MNSQ),one exhibited a high Outfit MNSQ value of 29.94,suggesting a potential misfit.Conclusion:This study demonstrated the acceptable validity and reliability of the Thai DEMMI.Further evaluation of its responsiveness to change is still recommended.展开更多
Bonding quality at the interface of solid propellant grains is crucial for the reliability and safety of solid rocket motors.Although bonding reliability is influenced by numerous factors,the lack of quantitative char...Bonding quality at the interface of solid propellant grains is crucial for the reliability and safety of solid rocket motors.Although bonding reliability is influenced by numerous factors,the lack of quantitative characterization of interface debonding mechanisms and the challenge of identifying key factors have made precise control of process variables difficult,resulting in unpredictable failure risks.This paper presents an improved fuzzy failure probability evaluation method that combines fuzzy fault tree analysis with expert knowledge,transforming process data into fuzzy failure probability to accurately assess debonding probabilities.The predictive model is constructed through a general regression neural network and optimized using the particle swarm optimization algorithm.Sensitivity analysis is conducted to identify key decision variables,including normal force,grain rotation speed,and adhesive weight,which are verified experimentally.Compared with classical models,the maximum error margin of the constructed reliability prediction model is only 0.02%,and it has high stability.The experimental results indicate that the main factors affecting debonding are processing roughness and coating uniformity.Controlling the key decision variable as the median resulted in a maximum increase of 200.7%in bonding strength.The feasibility of the improved method has been verified,confirming that identifying key decision variables has the ability to improve bonding reliability.The proposed method simplifies the evaluation of propellant interface bonding reliability under complex conditions by quantifying the relationship between process parameters and failure risk,enabling targeted management of key decision variables.展开更多
Ensuring the safety,resilience,and reliability of overhead low-voltage(LV)and medium-voltage(MV)power cables in aging infrastructure is vital for maintaining essential services and mitigating risks in electrical power...Ensuring the safety,resilience,and reliability of overhead low-voltage(LV)and medium-voltage(MV)power cables in aging infrastructure is vital for maintaining essential services and mitigating risks in electrical power distribution systems.This study introduces a novel framework that integrates fault tree analysis(FTA)/failure mode and effect analysis(FMEA)and a fuzzy inference system(FIS)to systematically address performance variability and enhance the operational life of these critical assets while ensuring safety and resilience.This structured framework employs risk-informed decision-making as well as reliability-based safety and resilience assurance,incorporating international standards and best practices.Under this methodology,the FIS models uncertainties in asset performance,using expert-defined rules and membership functions to categorize risk levels and assess failure severity.A case study is performed on overhead MV power cables,specifically the"Racoon"allaluminum alloy conductor(AAAC),demonstrating its practical implementation.The results reveal that for typical environmental conditions and design parameters,the yearly reliability of the conductor is nearly 1,indicating compliance with IEC standards.Furthermore,a risk matrix is developed using current carrying capacity(CCC),a failure mode obtained from the FTA as the probability of occurrence,and power shutdown duration(PSD)as the severity indicator.The risk matrix estimates the potential risk(PR)level based on CCC and PSD inputs.For example,for CCC=260 A and PSD=50 min,the resulting PR is 12.9,indicating a moderate risk exists.These risk levels guide appropriate resilience actions,ensuring proactive power cable management by identifying critical risks,prioritizing mitigation measures,and ensuring adaptability and compliance.This approach not only addresses the challenges of aging infrastructure but also contributes to long-term system integrity and operational reliability.展开更多
基金supported by the Major Program of National Natural Science Foundation of China(Grant No.42090055)the National Key ScientificInstruments and Equipment Development Projects of China(Grant No.41827808)the National Nature Science Foundation of China(Grant No.42207216).
文摘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.
基金supported by Istanbul Technical University(Project No.45698)supported through the“Young Researchers’Career Development Project-training of doctoral students”of the Croatian Science Foundation.
文摘This paper investigates the reliability of internal marine combustion engines using an integrated approach that combines Fault Tree Analysis(FTA)and Bayesian Networks(BN).FTA provides a structured,top-down method for identifying critical failure modes and their root causes,while BN introduces flexibility in probabilistic reasoning,enabling dynamic updates based on new evidence.This dual methodology overcomes the limitations of static FTA models,offering a comprehensive framework for system reliability analysis.Critical failures,including External Leakage(ELU),Failure to Start(FTS),and Overheating(OHE),were identified as key risks.By incorporating redundancy into high-risk components such as pumps and batteries,the likelihood of these failures was significantly reduced.For instance,redundant pumps reduced the probability of ELU by 31.88%,while additional batteries decreased the occurrence of FTS by 36.45%.The results underscore the practical benefits of combining FTA and BN for enhancing system reliability,particularly in maritime applications where operational safety and efficiency are critical.This research provides valuable insights for maintenance planning and highlights the importance of redundancy in critical systems,especially as the industry transitions toward more autonomous vessels.
基金the support from National Natural Science Foundation of China(No.52275153)the Frontier Technologies R&D Program of Jiangsu,China(No.BF2024068)+1 种基金The Fund of Prospective Layout of Scientific Research for Nanjing University of Aeronautics and Astronautics,ChinaResearch Fund of State Key Laboratory of Mechanics and Control for Aerospace Structures(Nanjing University of Aeronautics and Astronautics),China(Nos.MCAS-I-0425K01,MCAS-I-0423G01)。
文摘It is well recognized that Structural Health Monitoring(SHM)reliability evaluation is a key aspect that needs to be urgently addressed to promote the wide application of SHM methods.However,the existing studies typically transfer the Non-Destructive Testing/Evaluation(NDT/E)reliability metrics to SHM without a systematic analysis of where these metrics originated.Seldom attentions are paid to the evaluation conditions which are very important to apply these metrics.Aimed at this issue,a new condition control-based Dual-Reliability Evaluation(Dual-RE)method for SHM is proposed.This new method is proposed based on a systematic analysis of the whole framework of reliability evaluation from instrument to NDT,and emphasis is paid to the evaluation condition control.Based on these analyses,considering the special online application scenario of SHM,the proposed Dual-RE method contains two key components:Integrated Sensor-based SHM-RE(IS-SHM-RE)and Critical Service Condition-based SHM-RE(CSC-SHM-RE).ISSHM-RE evaluates the reliability of integrated SHM sensor and system themselves under approximate repeatability conditions,while CSC-SHM-RE assesses SHM reliability under the dominant uncertainties during service,namely intermediate conditions.To demonstrate the Dual-RE,crack monitoring by using the Guided Wave-based-SHM(GW-SHM)on aircraft lug structures is taken as a case study.Both the crack detection and sizing performance are evaluated from accuracy and uncertainty.
基金supported in part by the National Natural Science Foundation of China(62404110,62274033)Natural Science Foundation of Jiangsu Province(BK20221453)+1 种基金Fundamental Research Funds for the Central UniversitiesNatural Science Research Start-up Foundation of Recruiting Talents of Nanjing University of Posts and Telecommunications(NY223159)。
文摘In this work,we demonstrated the InSnO(ITO)TFTs passivated with SiO_(2)via the PECVD process compatible with large-area production for the first time.The passivated ITO TFTs with various channel thicknesses(t_(ch)=4,5,6 nm)exhibit excellent electrical performance and superior uniformity.The reliability properties of ITO TFTs were evaluated in detail under positive bias stress(PBS)conditions before and after passivation.Compared to the devices without passivation,the passivated devices have only 50%threshold voltage degradation(ΔV_(th))and 50%newly generated traps due to excellent isolation of the ambient atmosphere.The negligible performance degradation of ITO TFTs with passivation during negative bias stress(NBS)and negative bias temperature stress(NBTS)verifies the outstanding immunity to the water vapor of the SiO_(2)passivation layer.Overall,the ITO TFT with the t_(ch)of 6 nm and with SiO_(2)passivation exhibits the best performance in terms of electrical properties,uniformity,and reliability,which is promising in large-area production.
基金Funded by the National Natural Science Foundation of China(No.52178216)the Research on the Durability and Application of High-performance Concrete for Highway Engineering in the Cold and Arid Salt Areas of Northwest China(No.2022-24)the Construction Project of the Scientific Research Platform of Provincial Enterprises Supported by the Capital Operating Budget of Gansu Province(No.2023GZ018)。
文摘To study the durability of concrete in harsh environments in Northwest China,concrete was prepared with various durability-improving materials such as concrete anti-erosion inhibitor(SBT-TIA),acrylate polymer(AP),super absorbent resin(SAP).The erosion mode and internal deterioration mechanism under salt freeze-thaw cycle and dry-wet cycle were explored.The results show that the addition of enhancing materials can effectively improve the resistance of concrete to salt freezing and sulfate erosion:the relevant indexes of concrete added with X-AP and T-AP are improved after salt freeze-thaw cycles;concrete added with SBTTIA shows optimal sulfate corrosion resistance;and concrete added with AP displays the best resistance to salt freezing.Microanalysis shows that the increase in the number of cycles decreases the generation of internal hydration products and defects in concrete mixed with enhancing materials and improves the related indexes.Based on the Wiener model analysis,the reliability of concrete with different lithologies and enhancing materials is improved,which may provide a reference for the application of manufactured sand concrete and enhancing materials in Northwest China,especially for the study of the improvement effects and mechanism of enhancing materials on the performance of concrete.
基金National Natural Science Foundation of China(No.52375236)Fundamental Research Funds for the Central Universities of China(No.23D110316)。
文摘In reliability analyses,the absence of a priori information on the most probable point of failure(MPP)may result in overlooking critical points,thereby leading to biased assessment outcomes.Moreover,second-order reliability methods exhibit limited accuracy in highly nonlinear scenarios.To overcome these challenges,a novel reliability analysis strategy based on a multimodal differential evolution algorithm and a hypersphere integration method is proposed.Initially,the penalty function method is employed to reformulate the MPP search problem as a conditionally constrained optimization task.Subsequently,a differential evolution algorithm incorporating a population delineation strategy is utilized to identify all MPPs.Finally,a paraboloid equation is constructed based on the curvature of the limit-state function at the MPPs,and the failure probability of the structure is calculated by using the hypersphere integration method.The localization effectiveness of the MPPs is compared through multiple numerical cases and two engineering examples,with accuracy comparisons of failure probabilities against the first-order reliability method(FORM)and the secondorder reliability method(SORM).The results indicate that the method effectively identifies existing MPPs and achieves higher solution precision.
基金supported by the Research Project of China Academy of Railway Sciences Corporation Limited under Grant 2023YJ252.
文摘Purpose–This paper focuses on studying the reliability allocation for the railway system,aiming to improve the overall reliability of the railway system and ensure safety operation.Design/methodology/approach–In view of the complex structure of the railway system,involving many subsystems,this paper analyzes the close dynamic coupling effect between railway subsystems.Based on this,taking the railway system failure as the top event,a fault tree is constructed in this paper.Then,a reliability allocation method based on the fault tree is employed to allocate the reliability index.Finally,a numerical experiment is implemented to show the performance of the reliability allocation method.Findings–The results showed that each subsystem needs to improve its reliability to meet the specified railway system reliability requirements,and the traction power supply system is the most important subsystem,which is the most efficient in improving the reliability of the railway system.Originality/value–For the first time,starting from a holistic perspective of the system,reliability allocation is carried out based on the importance of each railway subsystem.
基金The National Key R&D Program Projects(Grant No.2022YFC2803601)the Natural Science Foundation of Shandong Province(Grant No.ZR2021YQ29)+1 种基金the Natural Science Foundation of Heilongjiang Province(Grant No.YQ2024E036)the Taishan Scholars Project(Grant No.tsqn202312317).
文摘Autonomous Underwater Vehicles(AUVs)are pivotal for deep-sea exploration and resource exploitation,yet their reliability in extreme underwater environments remains a critical barrier to widespread deployment.Through systematic analysis of 150 peer-reviewed studies employing mixed-methods research,this review yields three principal advancements to the reliability analysis of AUVs.First,based on the hierarchical functional division of AUVs into six subsystems(propulsion system,navigation system,communication system,power system,environmental detection system,and emergency system),this study systematically identifies the primary failure modes and potential failure causes of each subsystem,providing theoretical support for fault diagnosis and reliability optimization.Subsequently,a comprehensive review of AUV reliability analysis methods is conducted from three perspectives:analytical methods,simulated methods,and surrogate model methods.The applicability and limitations of each method are critically analyzed to offer insights into their suitability for engineering applications.Finally,the study highlights key challenges and research hotpots in AUV reliability analysis,including reliability analysis under limited data,AI-driven reliability analysis,and human reliability analysis.Furthermore,the potential of multi-sensor data fusion,edge computing,and advanced materials in enhancing AUV environmental adaptability and reliability is explored.
文摘Continuously increasing inflation is a major challenge in presenting reliable and relevant financial reports,especially in developing countries like Indonesia.This study aims to analyze the role of inflation accounting in increasing the reliability of financial reports during times of high inflation.With a qualitative-descriptive approach,this research examines two main methods in inflation accounting,namely General Price Level Accounting(GPLA)and Current Cost Accounting(CCA),and their impact on the value of assets,liabilities,income,and costs.The analysis results show that historical cost-based financial reports do not reflect actual economic conditions during inflation,so they can be misleading in decision making.The application of inflation accounting,through adjustments to purchasing power and current prices,has been proven to be able to increase the relevance and reliability of financial information.However,limitations in implementation in Indonesia are due to the lack of regulations and practical understanding regarding this method.Therefore,the application of inflation accounting is important in supporting the quality of financial reports and more accurate decision making amidst economic instability.
基金The authors extend their appreciation to the Ongoing Research Funding Program,number(ORF2025R705),King Saud University,Riyadh,Saudi Arabia,for funding this work.
文摘The study aims to determine the validity and reliability of the Wechsler Preschool and Primary Scale of Intelligence–Third Edition(WPPSI-III)scores in a sample of kindergarten and lower primary pupils from Khartoum State,Sudan.It also aims to examine whether test’s factor structure in this sample replicated that of the original WPPSI-III.The study sample consisted of 384 kindergarten and primary school children in Khartoum State(females=50%mean age=4.14,SD=1.37),selected using stratified random sampling across its seven localities:Khartoum,Jebel Awliya,Khartoum Bahri,East Nile,Omdurman,Ombada,Karari.For concurrent validation,the children additionally completed the Goodenough Draw-a-Man Test,and the Colored Progressive Matrices.WPPSI-III scores demonstrated high internal consistency across the subtest items.Confirmatory factor analysis indicators for total,verbal,and performance intelligence were all excellent.The scale also showed weak to strong score stability ranging from 0.25(weak)to 0.88(strong)based on the Spearman-Brown equation,0.25 to 0.75 based on the Guttman split-half method.The Cronbach’s alpha coefficient scores ranged from 0.54 to 0.93.The WPPSI-III and Goodenough Draw-a-Man Test scores concurrent validity scores were poor(0.05)to modest(0.31),and while those with the Colored Progressive Matrices test were poor(r=0.04–0.18).Thesefindings provide evidence to suggest that the WPPSI-III is appropriate for research use with kindergarten and lower primary school students in Khartoum State,Sudan.
基金Sichuan Provincial Nursing Research Project of the Sichuan Nursing Association in 2023(Project No.:H23028)。
文摘Objective:This study aims to develop an assessment tool for postoperative wound healing in adult patients with benign anal canal and rectal diseases and to validate its reliability and validity.Methods:Based on Levine’s Conservation Model as the theoretical framework,an item pool was formed through literature review,and the initial draft of the scale was refined through two rounds of Delphi expert consultation.A total of 200 postoperative patients were selected for item analysis,internal consistency testing,content validity,and structural validity analysis.Results:The final tool comprises four dimensions:energy conservation,structural integrity,personal integrity,and social integrity,with a total of 24 items.It demonstrates good content validity(I-CVI 0.82-1.00,S-CVI/Ave 0.95,S-CVI/UA 0.87)and excellent internal consistency(Cronbach’sαfor the overall scale was 0.934).Exploratory factor analysis revealed a KMO value of 0.931,Bartlett’s test of sphericityχ^(2)=4147.853(p<0.001),and four common factors were extracted,accounting for a cumulative variance contribution rate of 64.345%,indicating ideal structural validity.Conclusion:The results indicate that the assessment tool has good reliability and validity and can systematically evaluate postoperative wound healing,providing a scientific basis for clinical individualized nursing interventions.
文摘BACKGROUND During the gradual decline of physical and social functioning associated with end-stage renal disease,patients might experience a premonition of impending death,resulting in a series of pre-mourning grief responses called preparatory grief.The preparatory grief in advanced cancer patients(PGAC)scale is the most widely used preparatory grief scale for patients on hemodialysis in China.AIM To verify the reliability and validity of the PGAC scale in patients on hemodialysis.METHODS In total,327 patients undergoing regular hemodialysis in the blood purification center of three grade-A tertiary hospitals in Guangdong and Guizhou provinces were selected by convenience sampling.The assessment was administered using the general information questionnaire and the Chinese version of PGAC.SPSS 25.0 and Amos 24.0 were used for item analysis,confirmatory factor analysis(CFA),convergent validity,and internal consistency reliability estimation.RESULTS In the modified Chinese version of PGAC,7 dimensions covering 27 total items were retained.CFA revealed a good fit of the factor model(chi-square degree of freedom=2.056,standardized root mean square residual=0.0479,root mean square error of approximation=0.0570,GFI=0.872,AGFI=0.841,IFI=0.931,CFI=0.930,TLI=0.919).The factor loadings of the items ranged 0.503-0.884.The composite reliability ranged 0.664-0.914,and the average variance extracted ranged 0.366-0.747.Cronbach’sαof the scale was 0.945,and Cronbach’sαfor various dimensions ranged 0.662-0.914.CONCLUSION The modified PGAC has good reliability and validity,and it can effectively measure preparatory grief in patients on hemodialysis.
基金supported by the National Key Research and Development Program of China(Grant No.2021YFB2600504)the National Natural Science Foundation of China(Grant No.42072302)the Postdoctoral Fellowship Program of CPSF(Grant No.GZB20240533).
文摘Reliability analysis of soil slopes under rainfall is an important task for landslide risk assessment.Previous studies rarely contribute to the probabilistic analysis of slope stability under rainfall with reinforcement.A new method is suggested for reliability analysis of soil slopes stabilized with piles under rainfall.First,an efficient numerical model is exploited for slope stability analysis,where two types of slope failure modes,i.e.,plastic flow and local failure are considered.To address the blocking effect of piles during seepage analysis,the equivalent hydraulic conductivity of the pile area is estimated according to the effective medium theory.The stabilizing force of piles is investigated by an analytical approach.For saving computational effort,the response surface is established based on a multi-class classification model to predict two types of slope failure modes.Finally,uncertainties in soil parameters and rainfall events are both modelled,and the failure probability of soil slopes within a given time period is assessed through Monte Carlo simulation.An illustrative example is used to demonstrate the performance of the suggested method.It is found that the slope is mainly controlled by local failure.As the pile spacing increases,the likelihood of plastic flow significantly increases.As the piles are located near the slope crest,plastic flow is effectively prevented and the slope is better stabilized against rainfall.If rainfall uncertainties are not considered,the slope failure probability is significantly overestimated.Overall,this study can provide a useful guidance for the design of pile-stabilized slopes against rainfall infiltration.
文摘BACKGROUND The Victorian institute of sports assessment for patellar tendons questionnaire(VISA-P),a valid tool for patellar tendinopathy,has been used for patellofemoral pain(PFP).AIM To validate VISA-P in PFP.METHODS Study of validity,responsiveness and feasibility following COSMIN.Inclusion criteria:Subjects with PFP,aged 18 to 55.Agreement among 10 experts on the relevance and clarity of each item using Aiken's V coefficient determined content validity.An exploratory factorial analysis established structural validity.The correlation of VISA-P with knee injury and osteoarthritis outcome score for PFP and Osteoarthritis(KOOS-PF)and Kujala patellofemoral score(KPS;specific for PFP)analyzed the construct validity.Internal consistency was calculated with Cronbach'sαand test-retest reliability with the intraclass correlation coefficient(ICC).Feasibility considered the subjects'self-completion time.RESULTS The sample consisted of 103 knees from 73 subjects(47 female/26 male;aged 34.9±13 SD).The items were relevant and clear,with the exception of item-8,which didn't reach an acceptable level of agreement on clarity.Exploratory factorial analysis found a 2-factor solution,which explained 63.48%of the variance.VISAP achieved a strong and significant correlation with KOOS-PF(Spearman rho=0.826;P<0.001)and KPS(Spearman rho=0.771;P<0.001).The questionnaire showed adequate reliability(Cronbach'sα:0.752;ICC:0.934;P<0.0001;95%CI:0.902-0.955).The mean self-completion time was 232±0.52 SD seconds.CONCLUSION VISA-P proved to be valid and reliable to functionally assess PFP and/or chondromalacia patella.VISA-P is a feasible tool in the clinical and research environment,quick and easy to complete.
基金supported in part by the National Natural Science Foundation of China under Grant 62071073in part by the Fundamental Research Funds for Central Universities under Grant 2023CDJXY-041in part by the Foundation from Guangxi Key Laboratory of Optoelectronic Information Processing under Grant GD20201.
文摘The dynamic avalanche effect is a critical factor influencing the performance and reliability of the field-stop insulated gate bipolar transistors(FS-IGBT).Unclamped inductive switching(UIS)is the primary method for testing the dynamic avalanche capability of FS-IGBTs.Numerous studies have demonstrated that factors such as device structure,avalanche-generating current filaments,and electrical parameters influence the dynamic avalanche effect of the FS-IGBT.However,few studies have focused on enhancing the avalanche reliability of the FS-IGBT by adjusting circuit parameters during operation.In this paper,the dynamic avalanche effect of the FS-IGBT under UIS conditions is comprehensively investigated through a series of comparative experiments with varying circuit parameters,including bus voltage V_(DC),gate voltage V_(G),gate resistance R_(g),load inductance L,and temperature TC.Furthermore,a method to enhance the dynamic avalanche reliability of the FS-IGBT under UIS by optimizing circuit parameters is proposed.In practical applications,reducing gate voltage,increasing load inductance,and lowering temperature can effectively improve the dynamic avalanche capability of the FS-IGBT.
基金supported by National Natural Science Foundation of China(No.62201596)Research Planning Project of National University of Defense Technology(ZK22-45).
文摘The beyond fifth-generation Internet of Things requires more capable channel coding schemes to achieve high-reliability,low-complexity and lowlatency communications.The theoretical analysis of error-correction performance of channel coding functions as a significant way of optimizing the transmission reliability and efficiency.In this paper,the efficient estimation methods of the block error rate(BLER)performance for rate-compatible polar codes(RCPC)are proposed under several scenarios.Firstly,the BLER performance of RCPC is generally evaluated in the additive white Gaussian noise channels.That is further extended into the Rayleigh fading channel case using an equivalent estimation method.Moreover,with respect to the powerful decoder such as successive cancellation list decoding,the performance estimation is derived analytically based on the polar weight spectrum and BLER upper bounds.Theoretical evaluation and numerical simulation results show that the estimated performance can fit well the practical simulated results of RCPC under the objective conditions,verifying the validity of our proposed performance estimation methods.Furthermore,the application designs of the reliability estimation of RCPC are explored,particularly in the advantages of the signal-to-noise(SNR)estimation and throughput efficiency optimization of polar coded hybrid automatic repeat request.
文摘Nodal pricing is a critical mechanism in electricity markets,utilized to determine the cost of power transmission to various nodes within a distribution network.As power systems evolve to incorporate higher levels of renewable energy and face increasing demand fluctuations,traditional nodal pricing models often fall short to meet these new challenges.This research introduces a novel enhanced nodal pricing mechanism for distribution networks,integrating advanced optimization techniques and hybrid models to overcome these limitations.The primary objective is to develop a model that not only improves pricing accuracy but also enhances operational efficiency and system reliability.This study leverages cutting-edge hybrid algorithms,combining elements of machine learning with conventional optimization methods,to achieve superior performance.Key findings demonstrate that the proposed hybrid nodal pricing model significantly reduces pricing errors and operational costs compared to conventional methods.Through extensive simulations and comparative analysis,the model exhibits enhanced performance under varying load conditions and increased levels of renewable energy integration.The results indicate a substantial improvement in pricing precision and network stability.This study contributes to the ongoing discourse on optimizing electricity market mechanisms and provides actionable insights for policymakers and utility operators.By addressing the complexities of modern power distribution systems,our research offers a robust solution that enhances the efficiency and reliability of power distribution networks,marking a significant advancement in the field.
文摘Objective:This study aimed to translate the de Morton Mobility Index(DEMMI)into Thai and assess its measurement properties.Methods:The de Morton Mobility Index(DEMMI)was translated into Thai using a cross-cultural translation method.A cross-sectional study was conducted in four public hospitals in Thailand between January and March 2023.A total of 260 patients were recruited from outpatient clinics.Convergent and known-group validity were evaluated through hypothesis testing.Construct validity was examined using confirmatory factor analysis.Reliability was assessed using Cronbach’s a coefficient.We also employed the Rasch analysis to validate validity and person reliability.Results:Content validity was high(S-CVI=0.96,I-CVI range:0.80e1.00).Strong convergent validity was observed,with a significant correlation(r=0.761,P<0.001)between the Thai DEMMI and the Parker Mobility Scale(PMS).Known-group validity was evident,demonstrating differences in scores across various patient groups.A confirmatory factor analysis supported the hypothesized factor structure of the Thai DEMMI with good fit indices:χ^(2)(df=4)=5.101,P=0.2771;χ^(2)/df=1.275,RMSEA=0.033;CFI=0.998;TLI=0.995;SRMR=0.016.The Thai DEMMI exhibited high internal consistency(Cronbach’s a=0.88).Rasch analysis revealed good person reliability(0.91)and acceptable information-weighted fit means square statistic(0.73-1.06).However,most items showed good fit based on the outlier-sensitive fit means square statistics(Outfit MNSQ),one exhibited a high Outfit MNSQ value of 29.94,suggesting a potential misfit.Conclusion:This study demonstrated the acceptable validity and reliability of the Thai DEMMI.Further evaluation of its responsiveness to change is still recommended.
基金supported in part by the Equipment Development Pre-research Project funded by Equipment Development Department,PRC under Grant No.50923010501Fundamental Research Program of Shenyang Institute of Automation(SIA),Chinese Academy of Sciencess under Grant No.355060201。
文摘Bonding quality at the interface of solid propellant grains is crucial for the reliability and safety of solid rocket motors.Although bonding reliability is influenced by numerous factors,the lack of quantitative characterization of interface debonding mechanisms and the challenge of identifying key factors have made precise control of process variables difficult,resulting in unpredictable failure risks.This paper presents an improved fuzzy failure probability evaluation method that combines fuzzy fault tree analysis with expert knowledge,transforming process data into fuzzy failure probability to accurately assess debonding probabilities.The predictive model is constructed through a general regression neural network and optimized using the particle swarm optimization algorithm.Sensitivity analysis is conducted to identify key decision variables,including normal force,grain rotation speed,and adhesive weight,which are verified experimentally.Compared with classical models,the maximum error margin of the constructed reliability prediction model is only 0.02%,and it has high stability.The experimental results indicate that the main factors affecting debonding are processing roughness and coating uniformity.Controlling the key decision variable as the median resulted in a maximum increase of 200.7%in bonding strength.The feasibility of the improved method has been verified,confirming that identifying key decision variables has the ability to improve bonding reliability.The proposed method simplifies the evaluation of propellant interface bonding reliability under complex conditions by quantifying the relationship between process parameters and failure risk,enabling targeted management of key decision variables.
文摘Ensuring the safety,resilience,and reliability of overhead low-voltage(LV)and medium-voltage(MV)power cables in aging infrastructure is vital for maintaining essential services and mitigating risks in electrical power distribution systems.This study introduces a novel framework that integrates fault tree analysis(FTA)/failure mode and effect analysis(FMEA)and a fuzzy inference system(FIS)to systematically address performance variability and enhance the operational life of these critical assets while ensuring safety and resilience.This structured framework employs risk-informed decision-making as well as reliability-based safety and resilience assurance,incorporating international standards and best practices.Under this methodology,the FIS models uncertainties in asset performance,using expert-defined rules and membership functions to categorize risk levels and assess failure severity.A case study is performed on overhead MV power cables,specifically the"Racoon"allaluminum alloy conductor(AAAC),demonstrating its practical implementation.The results reveal that for typical environmental conditions and design parameters,the yearly reliability of the conductor is nearly 1,indicating compliance with IEC standards.Furthermore,a risk matrix is developed using current carrying capacity(CCC),a failure mode obtained from the FTA as the probability of occurrence,and power shutdown duration(PSD)as the severity indicator.The risk matrix estimates the potential risk(PR)level based on CCC and PSD inputs.For example,for CCC=260 A and PSD=50 min,the resulting PR is 12.9,indicating a moderate risk exists.These risk levels guide appropriate resilience actions,ensuring proactive power cable management by identifying critical risks,prioritizing mitigation measures,and ensuring adaptability and compliance.This approach not only addresses the challenges of aging infrastructure but also contributes to long-term system integrity and operational reliability.
