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Generalized nth-Order Perturbation Method Based on Loop Subdivision Surface Boundary Element Method for Three-Dimensional Broadband Structural Acoustic Uncertainty Analysis
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作者 Ruijin Huo Qingxiang Pei +1 位作者 Xiaohui Yuan Yanming Xu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期2053-2077,共25页
In this paper,a generalized nth-order perturbation method based on the isogeometric boundary element method is proposed for the uncertainty analysis of broadband structural acoustic scattering problems.The Burton-Mill... In this paper,a generalized nth-order perturbation method based on the isogeometric boundary element method is proposed for the uncertainty analysis of broadband structural acoustic scattering problems.The Burton-Miller method is employed to solve the problem of non-unique solutions that may be encountered in the external acoustic field,and the nth-order discretization formulation of the boundary integral equation is derived.In addition,the computation of loop subdivision surfaces and the subdivision rules are introduced.In order to confirm the effectiveness of the algorithm,the computed results are contrasted and analyzed with the results under Monte Carlo simulations(MCs)through several numerical examples. 展开更多
关键词 Perturbation method loop subdivision surface isogeometric boundary element method uncertainty analysis
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The prediction of projectile-target intersection for moving tank based on adaptive robust constraint-following control and interval uncertainty analysis
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作者 Cong Li Xiuye Wang +2 位作者 Yuze Ma Fengjie Xu Guolai Yang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期351-363,共13页
To improve the hit probability of tank at high speed,a prediction method of projectile-target intersection based on adaptive robust constraint-following control and interval uncertainty analysis is proposed.The method... To improve the hit probability of tank at high speed,a prediction method of projectile-target intersection based on adaptive robust constraint-following control and interval uncertainty analysis is proposed.The method proposed provides a novel way to predict the impact point of projectile for moving tank.First,bidirectional stability constraints and stability constraint-following error are constructed using the Udwadia-Kalaba theory,and an adaptive robust constraint-following controller is designed considering uncertainties.Second,the exterior ballistic ordinary differential equation with uncertainties is integrated into the controller,and the pointing control of stability system is extended to the impact-point control of projectile.Third,based on the interval uncertainty analysis method combining Chebyshev polynomial expansion and affine arithmetic,a prediction method of projectile-target intersection is proposed.Finally,the co-simulation experiment is performed by establishing the multi-body system dynamic model of tank and mathematical model of control system.The results demonstrate that the prediction method of projectile-target intersection based on uncertainty analysis can effectively decrease the uncertainties of system,improve the prediction accuracy,and increase the hit probability.The adaptive robust constraint-following control can effectively restrain the uncertainties caused by road excitation and model error. 展开更多
关键词 Tank stability control Constraint-following Adaptive robust control uncertainty analysis Prediction of projectile-target intersection
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Research Progress and Prospect of Tourism Carbon Emissions and Its Uncertainty Analysis Under the Goal of Low-Carbon Scenic Spots
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作者 Aihong Wang Qiguang Lyu 《Proceedings of Business and Economic Studies》 2023年第2期25-32,共8页
Under the dual carbon goal,China Certified Emissions Reductions(CCER)and the national carbon market have become important means of emission reduction and control.The tourism industry is a strategic pillar industry of ... Under the dual carbon goal,China Certified Emissions Reductions(CCER)and the national carbon market have become important means of emission reduction and control.The tourism industry is a strategic pillar industry of China’s national economy,and scenic spots are the main sites of tourism activities.Research on carbon emissions in scenic spots is of great significance for the construction of low-carbon scenic spots and the realization of the dual carbon goal.In this paper,the research on carbon emissions in tourism is reviewed,the current research progress is discussed,and further prospects are made.The research on tourism carbon emissions in China has a good foundation and achieved certain results.However,there are few studies on micro-scales such as scenic spots.The statistical data caliber and measurement methods of carbon emissions are not uniform,and there is a general lack of uncertainty analysis.Future research should focus on building a multi-spatial dimension research system,unifying the statistical caliber and measurement methods of carbon emission data,increasing uncertainty analysis,and ensuring the robustness of research results. 展开更多
关键词 Low-carbon scenic spot Carbon emissions uncertainty analysis
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Third Order Adjoint Sensitivity and Uncertainty Analysis of an OECD/NEA Reactor Physics Benchmark: III. Response Moments 被引量:3
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作者 Ruixian Fang Dan Gabriel Cacuci 《American Journal of Computational Mathematics》 2020年第4期559-570,共12页
The (180)<sup>3</sup> third-order mixed sensitivities of the leakage response of a polyethylene-reflected plutonium (PERP) experimental benchmark with respect to the benchmark’s 180 microscopic total cros... The (180)<sup>3</sup> third-order mixed sensitivities of the leakage response of a polyethylene-reflected plutonium (PERP) experimental benchmark with respect to the benchmark’s 180 microscopic total cross sections have been computed in accompanying works [1] [2]. This work quantifies the contributions of these (180)<sup>3</sup> third-order mixed sensitivities to the PERP benchmark’s leakage response distribution moments (expected value, variance and skewness) and compares these contributions to those stemming from the corresponding first- and second-order sensitivities of the PERP benchmark’s leakage response with respect to the total cross sections. The numerical results obtained in this work reveal that the importance of the 3<sup>rd</sup>-order sensitivities can surpass the importance of the 1<sup>st</sup>- and 2<sup>nd</sup>-order sensitivities when the parameters’ uncertainties increase. In particular, for a uniform standard deviation of 10% of the microscopic total cross sections, the 3<sup>rd</sup>-order sensitivities contribute 80% to the response variance, whereas the contribution stemming from the 1st- and 2nd-order sensitivities amount only to 2% and 18%, respectively. Consequently, neglecting the 3<sup>rd</sup>-order sensitivities could cause a very large non-conservative error by under-reporting the response variance by a factor of 506%. The results obtained in this work also indicate that the effects of the 3<sup>rd</sup>-order sensitivities are to reduce the response’s skewness in parameter space, rendering the distribution of the leakage response more symmetric about its expected value. The results obtained in this work are the first such results ever published in reactor physics. Since correlations among the group-averaged microscopic total cross sections are not available, only the effects of typical standard deviations for these cross sections could be considered. Due to this lack of correlations among the cross sections, the effects of the <em>mixed</em> 3<sup>rd</sup>-order sensitivities could not be quantified exactly at this time. These effects could be quantified only when correlations among the group-averaged microscopic total cross sections would be obtained experimentally by the nuclear physics community. 展开更多
关键词 Polyethylene-Reflected Plutonium Sphere 3rd-Order Sensitivities 1st-Order 2nd-Order and 3rd-Order uncertainty analysis Microscopic Total Cross Sections Expected Value Variance and Skewness of Response Distribution
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Calibration chain design based on integrating sphere transfer radiometer for SI-traceable on-orbit spectral radiometric calibration and its uncertainty analysis 被引量:1
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作者 赵维宁 方伟 +2 位作者 孙立微 崔立红 王玉鹏 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第9期276-283,共8页
In order to satisfy the requirement of SI-traceable on-orbit absolute radiation calibration transfer with high accuracy for satellite remote sensors,a transfer chain consisting of a fiber coupling monochromator(FBM)... In order to satisfy the requirement of SI-traceable on-orbit absolute radiation calibration transfer with high accuracy for satellite remote sensors,a transfer chain consisting of a fiber coupling monochromator(FBM) and an integrating sphere transfer radiometer(ISTR) was designed in this paper.Depending on the Sun,this chain based on detectors provides precise spectral radiometric calibration and measurement to spectrometers in the reflective solar band(RSB) covering 300–2500 nm with a spectral bandwidth of 0.5–6 nm.It shortens the traditional chain based on lamp source and reduces the calibration uncertainty from 5% to 0.5% by using the cryogenic radiometer in space as a radiometric benchmark and trap detectors as secondary standard.This paper also gives a detailed uncertainty budget with reasonable distribution of each impact factor,including the weak spectral signal measurement with uncertainty of 0.28%.According to the peculiar design and comprehensive uncertainty analysis,it illustrates that the spectral radiance measurement uncertainty of the ISTR system can reach to 0.48%.The result satisfies the requirements of SI-traceable on-orbit calibration and has wider significance for expanding the application of the remote sensing data with high-quality. 展开更多
关键词 SI-traceable calibration on-orbit high-accuracy transfer chain integrating sphere transfer radiometer uncertainty analysis
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Evolution-Based Uncertainty Analysis for Incline Hoist
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作者 石博强 申焱华 《Journal of Donghua University(English Edition)》 EI CAS 2015年第6期995-997,共3页
The effect of uncertainty and its evolution with time on the incline hoist reliability are investigated in this paper.The performance of incline hoist is changed over time and gradually degraded.The degradation will i... The effect of uncertainty and its evolution with time on the incline hoist reliability are investigated in this paper.The performance of incline hoist is changed over time and gradually degraded.The degradation will influence the safe usage and reliability of incline hoist.Degradation process can be described by stochastic process.The degradation process of incline hoist is modeled in geometric Brownian motions(GBM),and the drift rate and diffusion rate of this process can reflect the failure extent and fluctuation of the system.Evolution-based uncertainty analysis(EBUA)method is proposed to describe the dynamic reliability of the incline hoist,and the system of incline hoist can be designed with the specified reliability value at the given time. 展开更多
关键词 evolution-based uncertainty analysis(EBUA) reliability incline hoist geometric Brownian motions(GBM)
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Mixed uncertainty analysis of polycyclic aromatic hydrocarbon inhalation and risk assessment in ambient air of Beijing 被引量:7
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作者 College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China GUO Huaicheng +3 位作者 LIU Yong HUANG Kai WANG Zhen ZHAN Xinye 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第4期505-512,共8页
This article presents the application of an integrated method that estimates the dispersion of polycyclic aromatic hydrocarbons (PAHs) in air, and assesses the human health risk associated with PAHs inhalation. An u... This article presents the application of an integrated method that estimates the dispersion of polycyclic aromatic hydrocarbons (PAHs) in air, and assesses the human health risk associated with PAHs inhalation. An uncertainty analysis method consisting of three components were applied in this study, where the three components include a bootstrapping method for analyzing the whole process associated uncertainty, an inhalation rate (IR) representation for evaluating the total PAH inhalation risk for human health, and a normally distributed absorption fraction (AF) ranging from 0% to 100% to represent the absorption capability of PAHs in human body. Using this method, an integrated process was employed to assess the health risk of the residents in Beijing, China, from inhaling PAHs in the air. The results indicate that the ambient air PAHs in Beijing is an important contributor to human health impairment, although over 68% of residents seem to be safe from daily PAH carcinogenic inhalation. In general, the accumulated daily inhalation amount is relatively higher for male and children at 10 years old of age than for female and children at 6 years old. In 1997, about 1.73% cancer sufferers in Beijing were more or less related to ambient air PAHs inhalation. At 95% confidence interval, approximately 272-309 individual cancer incidences can be attributed to PAHs pollution in the air. The probability of greater than 500 cancer occurrence is 15.3%. While the inhalation of ambient air PAHs was shown to be an important factor responsible for higher cancer occurrence in Beijing, while the contribution might not be the most significant one. 展开更多
关键词 polycyclic aromatic hydrocarbons (PAHs) uncertainty analysis human health risk
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Multi-parameters uncertainty analysis of logistic support process based on GERT 被引量:6
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作者 Yong Wu Xing Pan +2 位作者 Rui Kang Congjiao He Liming Gong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第6期1011-1019,共9页
The uncertainty analysis is an effective sensitivity analysis method for system model analysis and optimization. However,the existing single-factor uncertainty analysis methods are not well used in the logistic suppor... The uncertainty analysis is an effective sensitivity analysis method for system model analysis and optimization. However,the existing single-factor uncertainty analysis methods are not well used in the logistic support systems with multiple decision-making factors. The multiple transfer parameters graphical evaluation and review technique(MTP-GERT) is used to model the logistic support process in consideration of two important factors, support activity time and support activity resources, which are two primary causes for the logistic support process uncertainty. On this basis,a global sensitivity analysis(GSA) method based on covariance is designed to analyze the logistic support process uncertainty. The aircraft support process is selected as a case application which illustrates the validity of the proposed method to analyze the support process uncertainty, and some feasible recommendations are proposed for aircraft support decision making on carrier. 展开更多
关键词 logistic support process uncertainty analysis graphi-cal evaluation and review technique(GERT) sensitivity analysis
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Sensitivity and Uncertainty Analysis of Regional Marine Ecosystem Services Value 被引量:3
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作者 SHI Honghua ZHENG Wei +1 位作者 WANG Zongling DING Dewen 《Journal of Ocean University of China》 SCIE CAS 2009年第2期150-154,共5页
Marine ecosystem services are the benefits which people obtain from the marine ecosystem,including provisioning services,regulating services,cultural services and supporting services. The human species,while buffered ... Marine ecosystem services are the benefits which people obtain from the marine ecosystem,including provisioning services,regulating services,cultural services and supporting services. The human species,while buffered against environmental changes by culture and technology,is fundamentally dependent on the flow of ecosystem services. Marine ecosystem services become increasingly valuable as the terrestrial resources become scarce. The value of marine ecosystem services is the monetary flow of ecosystem services on specific temporal and spatial scales,which often changes due to the variation of the goods prices,yields and the status of marine exploitation. Sensitivity analysis is to study the relationship between the value of marine ecosystem services and the main factors which affect it. Uncertainty analysis based on varying prices,yields and status of marine exploitation was carried out. Through uncertainty analysis,a more credible value range instead of a fixed value of marine ecosystem services was obtained in this study. Moreover,sensitivity analysis of the marine ecosystem services value revealed the relative importance of different factors. 展开更多
关键词 marine ecosystem ecosystem services value sensitivity analysis uncertainty analysis
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Application of SWAT Model to the Olifants Basin: Calibration, Validation and Uncertainty Analysis 被引量:3
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作者 Charles Gyamfi Julius Musyoka Ndambuki Ramadhan Wanjala Salim 《Journal of Water Resource and Protection》 2016年第3期397-410,共14页
The application of the Soil and Water Assessment Tool (SWAT) to the Olifants Basin in South Africa was the focus of our study with emphasis on calibration, validation and uncertainty analysis. The Basin was discretize... The application of the Soil and Water Assessment Tool (SWAT) to the Olifants Basin in South Africa was the focus of our study with emphasis on calibration, validation and uncertainty analysis. The Basin was discretized into 23 sub-basins and 226 Hydrologic Response Units (HRUs) using 3 arc second (90 m × 90 m) pixel resolution SRTM DEM with stream gauge B7H015 as the Basin outlet. Observed stream flow data at B7H015 were used for model calibration (1988-2001) and validation (2002-2013) using the split sample approach. Relative global sensitivity analysis using SUFI-2 algorithm was used to determine sensitive parameters to stream flow for calibration of the model. Performance efficiency of the Olifants SWAT model was assessed using Nash-Sutcliffe (NSE), coefficient of determination (R<sup>2</sup>), Percent Bias (PBIAS) and Root Mean Square Error-Observation Standard deviation Ratio (RSR). Sensitivity analysis revealed in decreasing order of significance, runoff curve number (CN2), alpha bank factor (ALPHA_BNK), soil evaporation compensation factor (ESCO), soil available water capacity (SOIL_AWC, mm H<sub>2</sub>O/mm soil), groundwater delay (GW_ DELAY, days) and groundwater “revap” coefficient (GW_REVAP) to be the most sensitive parameters to stream flow. Analysis of the model during the calibration period gave the following statistics;NSE = 0.88;R<sup>2</sup> = 0.89;PBIAS = -11.49%;RSR = 0.34. On the other hand, statistics during the validation period were NSE = 0.67;R<sup>2 </sup>= 0.79;PBIAS = -20.69%;RSR = 0.57. The observed statistics indicate the applicability of the SWAT model in simulating the hydrology of the Olifants Basin and therefore can be used as a Decision Support Tool (DST) by water managers and other relevant decisions making bodies to influence policy directions on the management of watershed processes especially water resources. 展开更多
关键词 CALIBRATION VALIDATION uncertainty analysis Olifants Basin SWAT Model
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An Uncertainty Analysis Method for Artillery Dynamics with Hybrid Stochastic and Interval Parameters 被引量:1
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作者 Liqun Wang Zengtao Chen Guolai Yang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第2期479-503,共25页
This paper proposes a non-intrusive uncertainty analysis method for artillery dynamics involving hybrid uncertainty using polynomial chaos expansion(PCE).The uncertainty parameters with sufficient information are rega... This paper proposes a non-intrusive uncertainty analysis method for artillery dynamics involving hybrid uncertainty using polynomial chaos expansion(PCE).The uncertainty parameters with sufficient information are regarded as stochastic variables,whereas the interval variables are used to treat the uncertainty parameters with limited stochastic knowledge.In this method,the PCE model is constructed through the Galerkin projection method,in which the sparse grid strategy is used to generate the integral points and the corresponding integral weights.Through the sampling in PCE,the original dynamic systems with hybrid stochastic and interval parameters can be transformed into deterministic dynamic systems,without changing their expressions.The yielded PCE model is utilized as a computationally efficient,surrogate model,and the supremum and infimum of the dynamic responses over all time iteration steps can be easily approximated through Monte Carlo simulation and percentile difference.A numerical example and an artillery exterior ballistic dynamics model are used to illustrate the feasibility and efficiency of this approach.The numerical results indicate that the dynamic response bounds obtained by the PCE approach almost match the results of the direct Monte Carlo simulation,but the computational efficiency of the PCE approach is much higher than direct Monte Carlo simulation.Moreover,the proposed method also exhibits fine precision even in high-dimensional uncertainty analysis problems. 展开更多
关键词 uncertainty propagation and analysis artillery dynamics hybrid stochastic and interval uncertainty polynomial chaos expansion ordinary differential equations
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Stratum Dip Analysis and DMO Correction of Zero-Offset VSP Data
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作者 Wang Bao-li Zhu Guang-ming 《石油地球物理勘探》 EI CSCD 北大核心 2009年第A02期59-65,共7页
关键词 VSP数据 零偏移距 地层分析 DMO 地层倾角 校正 数据处理 地层倾斜
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Poisson rectangular pulse(PRP)model establishment based on uncertainty analysis of urban residential water consumption patterns 被引量:1
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作者 Jiaxin Zhang Dragan Savic +2 位作者 Qiang Xu Kuo Liu Zhimin Qiang 《Environmental Science and Ecotechnology》 SCIE 2024年第2期53-59,共7页
The commonly used Poisson rectangular pulse(PRP)model,employed for simulating high-resolution residential water consumption patterns(RWCPs),relies on calibration via medium-resolution RWCPs obtained from practical mea... The commonly used Poisson rectangular pulse(PRP)model,employed for simulating high-resolution residential water consumption patterns(RWCPs),relies on calibration via medium-resolution RWCPs obtained from practical measurements.This introduces inevitable uncertainty stemming from the measured RWCPs,which consequently impacts the precision of model simulations.Here we enhance the accuracy of the PRP model by addressing the uncertainty of RWCPs.We established a critical sampling size of 2000 household water consumption patterns(HWCPs)with a data logging interval(DLI)of 15 min to attain dependable RWCPs.Through Genetic Algorithm calibration,the optimal values of the PRP model's parameters were determined:pulse frequency lλ=91 d^(-1),mean of pulse intensity E(I)=0.346 m^(3) h^(-1),standard deviation of pulse intensity STD(I)=0.292 m^(3) h^(-1),mean of pulse duration E(D)=40 s,and standard deviation of pulse duration STD(D)=55 s.Furthermore,validation was conducted at both HWCP and RWCP levels.We recommend a sampling size of2000 HWCPs and a DLI of30 min for PRP model calibration to balance simulation precision and practical implementation.This study significantly advances the theoretical foundation and real-world application of the PRP model,enhancing its role in urban water supply system management. 展开更多
关键词 Residential water consumption pattern uncertainty analysis Poisson rectangular pulse model Model establishment
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Uncertainty quantification of inverse analysis for geomaterials using probabilistic programming
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作者 Hongbo Zhao Shaojun Li +3 位作者 Xiaoyu Zang Xinyi Liu Lin Zhang Jiaolong Ren 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期895-908,共14页
Uncertainty is an essentially challenging for safe construction and long-term stability of geotechnical engineering.The inverse analysis is commonly utilized to determine the physico-mechanical parameters.However,conv... Uncertainty is an essentially challenging for safe construction and long-term stability of geotechnical engineering.The inverse analysis is commonly utilized to determine the physico-mechanical parameters.However,conventional inverse analysis cannot deal with uncertainty in geotechnical and geological systems.In this study,a framework was developed to evaluate and quantify uncertainty in inverse analysis based on the reduced-order model(ROM)and probabilistic programming.The ROM was utilized to capture the mechanical and deformation properties of surrounding rock mass in geomechanical problems.Probabilistic programming was employed to evaluate uncertainty during construction in geotechnical engineering.A circular tunnel was then used to illustrate the proposed framework using analytical and numerical solution.The results show that the geomechanical parameters and associated uncertainty can be properly obtained and the proposed framework can capture the mechanical behaviors under uncertainty.Then,a slope case was employed to demonstrate the performance of the developed framework.The results prove that the proposed framework provides a scientific,feasible,and effective tool to characterize the properties and physical mechanism of geomaterials under uncertainty in geotechnical engineering problems. 展开更多
关键词 Geological engineering Geotechnical engineering Inverse analysis uncertainty quantification Probabilistic programming
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Uncertainty and sensitivity analysis of in-vessel phenomena under severe accident mitigation strategy based on ISAA-SAUP program
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作者 Hao Yang Ji-Shen Li +2 位作者 Zhi-Ran Zhang Bin Zhang Jian-Qiang Shan 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期108-123,共16页
The phenomenology involved in severe accidents in nuclear reactors is highly complex.Currently,integrated analysis programs used for severe accident analysis heavily rely on custom empirical parameters,which introduce... The phenomenology involved in severe accidents in nuclear reactors is highly complex.Currently,integrated analysis programs used for severe accident analysis heavily rely on custom empirical parameters,which introduce considerable uncertainty.Therefore,in recent years,the field of severe accidents has shifted its focus toward applying uncertainty analysis methods to quantify uncertainty in safety assessment programs,known as“best estimate plus uncertainty(BEPU).”This approach aids in enhancing our comprehension of these programs and their further development and improvement.This study concentrates on a third-generation pressurized water reactor equipped with advanced active and passive mitigation strategies.Through an Integrated Severe Accident Analysis Program(ISAA),numerical modeling and uncertainty analysis were conducted on severe accidents resulting from large break loss of coolant accidents.Seventeen uncertainty parameters of the ISAA program were meticulously screened.Using Wilks'formula,the developed uncertainty program code,SAUP,was employed to carry out Latin hypercube sampling,while ISAA was employed to execute batch calculations.Statistical analysis was then conducted on two figures of merit,namely hydrogen generation and the release of fission products within the pressure vessel.Uncertainty calculations revealed that hydrogen production and the fraction of fission product released exhibited a normal distribution,ranging from 182.784 to 330.664 kg and from 15.6 to 84.3%,respectively.The ratio of hydrogen production to reactor thermal power fell within the range of 0.0578–0.105.A sensitivity analysis was performed for uncertain input parameters,revealing significant correlations between the failure temperature of the cladding oxide layer,maximum melt flow rate,size of the particulate debris,and porosity of the debris with both hydrogen generation and the release of fission products. 展开更多
关键词 Gen-III PWR Severe accident mitigation Wilks’formula HYDROGEN Fission products uncertainty and sensitivity analysis
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Bibliometric Review of Biodiversity Offsetting During 1992-2019
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作者 YU Shuling CUI Baoshan +2 位作者 XIE Chengjie MAN Ying FU Jing 《Chinese Geographical Science》 SCIE CSCD 2022年第2期189-203,共15页
Biodiversity offsetting plays a crucial role in managing the impacts of development on natural habitats. Developers, conservation groups, governments and financial institutions have used biodiversity offsetting to des... Biodiversity offsetting plays a crucial role in managing the impacts of development on natural habitats. Developers, conservation groups, governments and financial institutions have used biodiversity offsetting to design measurable conservation actions to compensate for significant residual adverse biodiversity impacts arising from development. However, the concepts and methodologies of biodiversity offsetting have rarely been systematically reviewed, and best practices are still lacking. This hinders the development and applications of this field, and makes it difficult for new researchers to learn, develop, and apply biodiversity offsetting. This paper aims to review research progress on biodiversity offsetting during the period of 1992 to 2019. We mainly used bibliometric analysis and social network analysis methods to expose the topic diversity, development and promotion of this research field, and assess collaboration among biodiversity offsetting scholars. Our research identified 1190 records, and revealed that the total number of publications increased rapidly since 2002. The most productive journal, country, and author were Biological Conservation, USA, and Dr. Maron M of University of Queensland, respectively. Co-author analysis identified that the 23 authors most relevant to biodiversity offsetting were involved in a collaboration network. And they were mainly from 30 countries in a collaboration network, and the authors from USA, Australia and the United Kingdom have the most cooperation, which mainly driven by policy related to biodiversity offsetting. Our review shows that biodiversity offsetting research is at an early stage of rapid development with topically diverse and collaborative science domains. The majority of studies focus on terrestrial environments, which makes the implementation of aquatic ecosystem is more difficult. Theoretical problems and the implications of research evolution and social network in biodiversity offsetting are discussed, and further development of the theory and methodologies of biodiversity offsetting and management was recommend. 展开更多
关键词 academic influence biodiversity offsetting COMPENSATION bibliometric analysis social network analysis
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Optimization for aerodynamic performance of double serpentine nozzles with spanwise offsets using Taguchi-based CFD analysis 被引量:1
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作者 Xuyong ZHANG Yong SHAN +1 位作者 Jingzhou ZHANG Zhongcheng WU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第5期1-17,共17页
Serpentine nozzles are widely used in combat aircraft to realize strong stealth characteristics.Based on the layout characteristics within a confined space,a series of double serpentine nozzles with spanwise offsets a... Serpentine nozzles are widely used in combat aircraft to realize strong stealth characteristics.Based on the layout characteristics within a confined space,a series of double serpentine nozzles with spanwise offsets are established.Using computational fluid dynamics and Taguchi method,the influence mechanisms of the Distribution of Area(DA),Distributions of Centerline for the first and second‘S’sections in the Vertical direction(DCV1 and DCV2),and Distribution of Centerline in the Spanwise direction(DCS)are analyzed.The impact of these factors on the total pressure recovery coefficient can be ranked as DA>DCV2>DCS>DCV1,whereas their impacts on the discharge coefficient and axial thrust coefficient can be ranked as DCV2>DCS>DA>DCV1.Considering the statistical significance of these factors,a nozzle in which DA changes rapidly at the exit and DCV1,DCV2,and DCS change rapidly at the entrance gives the best aerodynamic performance.Compared to the worst configuration,the total pressure recovery coefficient,discharge coefficient,and axial thrust coefficient are improved by 1.6%,3.5%and 3.6%,respectively.DA influences the gas flow acceleration in the entire serpentine channel,resulting in different wall shear stress and friction losses.The various centerline distributions influence the gas flow acceleration effects and form complex wave structures in the constantarea extension section,resulting in different local and friction losses. 展开更多
关键词 AERODYNAMICS analysis of Variance(ANOVA) Computational Fluid Dynamics(CFD) Double serpentine nozzle Spanwise offset Taguchi methods
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Rockfill material uncertainty inversion analysis of concrete-faced rockfill dams using stacking ensemble strategy and Jaya optimizer 被引量:1
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作者 Qin Ke Ming-chao Li +1 位作者 Qiu-bing Ren Wen-chao Zhao 《Water Science and Engineering》 EI CAS CSCD 2023年第4期419-428,共10页
Numerical simulation of concrete-faced rockfill dams(CFRDs)considering the spatial variability of rockfill has become a popular research topic in recent years.In order to determine uncertain rockfill properties effici... Numerical simulation of concrete-faced rockfill dams(CFRDs)considering the spatial variability of rockfill has become a popular research topic in recent years.In order to determine uncertain rockfill properties efficiently and reliably,this study developed an uncertainty inversion analysis method for rockfill material parameters using the stacking ensemble strategy and Jaya optimizer.The comprehensive implementation process of the proposed model was described with an illustrative CFRD example.First,the surrogate model method using the stacking ensemble algorithm was used to conduct the Monte Carlo stochastic finite element calculations with reduced computational cost and improved accuracy.Afterwards,the Jaya algorithm was used to inversely calculate the combination of the coefficient of variation of rockfill material parameters.This optimizer obtained higher accuracy and more significant uncertainty reduction than traditional optimizers.Overall,the developed model effectively identified the random parameters of rockfill materials.This study provided scientific references for uncertainty analysis of CFRDs.In addition,the proposed method can be applied to other similar engineering structures. 展开更多
关键词 CFRD uncertainty inversion analysis Stochastic finite element Surrogate model Stacking ensemble Jaya algorithm
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Uncertainty-Aware Deep Learning: A Promising Tool for Trustworthy Fault Diagnosis
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作者 Jiaxin Ren Jingcheng Wen +3 位作者 Zhibin Zhao Ruqiang Yan Xuefeng Chen Asoke K.Nandi 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1317-1330,共14页
Recently,intelligent fault diagnosis based on deep learning has been extensively investigated,exhibiting state-of-the-art performance.However,the deep learning model is often not truly trusted by users due to the lack... Recently,intelligent fault diagnosis based on deep learning has been extensively investigated,exhibiting state-of-the-art performance.However,the deep learning model is often not truly trusted by users due to the lack of interpretability of“black box”,which limits its deployment in safety-critical applications.A trusted fault diagnosis system requires that the faults can be accurately diagnosed in most cases,and the human in the deci-sion-making loop can be found to deal with the abnormal situa-tion when the models fail.In this paper,we explore a simplified method for quantifying both aleatoric and epistemic uncertainty in deterministic networks,called SAEU.In SAEU,Multivariate Gaussian distribution is employed in the deep architecture to compensate for the shortcomings of complexity and applicability of Bayesian neural networks.Based on the SAEU,we propose a unified uncertainty-aware deep learning framework(UU-DLF)to realize the grand vision of trustworthy fault diagnosis.Moreover,our UU-DLF effectively embodies the idea of“humans in the loop”,which not only allows for manual intervention in abnor-mal situations of diagnostic models,but also makes correspond-ing improvements on existing models based on traceability analy-sis.Finally,two experiments conducted on the gearbox and aero-engine bevel gears are used to demonstrate the effectiveness of UU-DLF and explore the effective reasons behind. 展开更多
关键词 Out-of-distribution detection traceability analysis trustworthy fault diagnosis uncertainty quantification.
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On the Application of Mixed Models of Probability and Convex Set for Time-Variant Reliability Analysis
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作者 Fangyi Li Dachang Zhu Huimin Shi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1981-1999,共19页
In time-variant reliability problems,there are a lot of uncertain variables from different sources.Therefore,it is important to consider these uncertainties in engineering.In addition,time-variant reliability problems... In time-variant reliability problems,there are a lot of uncertain variables from different sources.Therefore,it is important to consider these uncertainties in engineering.In addition,time-variant reliability problems typically involve a complexmultilevel nested optimization problem,which can result in an enormous amount of computation.To this end,this paper studies the time-variant reliability evaluation of structures with stochastic and bounded uncertainties using a mixed probability and convex set model.In this method,the stochastic process of a limit-state function with mixed uncertain parameters is first discretized and then converted into a timeindependent reliability problem.Further,to solve the double nested optimization problem in hybrid reliability calculation,an efficient iterative scheme is designed in standard uncertainty space to determine the most probable point(MPP).The limit state function is linearized at these points,and an innovative random variable is defined to solve the equivalent static reliability analysis model.The effectiveness of the proposed method is verified by two benchmark numerical examples and a practical engineering problem. 展开更多
关键词 Mixed uncertainty probability model convex model time-variant reliability analysis
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