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Board-invited review: Sensitivity and responses of functional groups to feed processing methods on a molecular basis 被引量:2
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作者 Peiqiang Yu 《Journal of Animal Science and Biotechnology》 SCIE CAS 2013年第1期1-4,共4页
In complex feed structures, there exist main chemical functional groups which are associated with nutrient utilization and availability and functionality. Each functional group has unique molecular structure therefore... In complex feed structures, there exist main chemical functional groups which are associated with nutrient utilization and availability and functionality. Each functional group has unique molecular structure therefore produce unique molecular vibration spectral profile. Feed processing has been used to improve nutrient utilization for many years. However, to date, there was little study on processing-induced changes of feed intrinsic structure and functional groups on a molecular basis within intact tissue. This is because limited research technique is available to study inherent structure on a molecular basis. Recently bioanalytical techniques: such as Synchrotron Infrared Microspectroscopy as well as Diffuse Reflectance Infrared Fourier Transform molecular spectroscopy have been developed. These techniques enable to detect molecular structure change within intact tissues. These techniques can prevent destruction or alteration of the intrinsic protein structures during processing for analysis. However, these techniques have not been used in animal feed and nutrition research. The objective of this review was show that with the advanced technique, sensitivity and responses of functional groups to feed processing on a molecular basis could be detected in my research team. These functional groups are highly associated with nutrient utilization in animals. 展开更多
关键词 sensitivity and responses of functional groups Molecular structures Feed processing Nutrient utilizationand availability
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PID Controller Design Based on the Time Domain Information of Robust IMC Controller Using Maximum Sensitivity 被引量:14
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作者 靳其兵 刘切 +2 位作者 王琪 田育奇 王元飞 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第5期529-536,共8页
The IMC(Internal Model Control) controller based on robust tuning can improve the robustness and dynamic performance of the system.In this paper,the robustness degree of the control system is investigated based on Max... The IMC(Internal Model Control) controller based on robust tuning can improve the robustness and dynamic performance of the system.In this paper,the robustness degree of the control system is investigated based on Maximum Sensitivity(Ms) in depth.And the analytical relationship is obtained between the robustness specification and controller parameters,which gives a clear design criterion to robust IMC controller.Moreover,a novel and simple IMC-PID(Proportional-Integral-Derivative) tuning method is proposed by converting the IMC controller to PID form in terms of the time domain rather than the frequency domain adopted in some conventional IMC-based methods.Hence,the presented IMC-PID gives a good performance with a specific robustness degree.The new IMC-PID method is compared with other classical IMC-PID rules,showing the flexibility and feasibility for a wide range of plants. 展开更多
关键词 internal model control-PID ROBUSTNESS parameter tuning maximum sensitivity function
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Infinity Norm Measurement of Sensitivity for Closed-Loop Systems Using Chirp as Excitation
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作者 史大威 王军政 《Journal of Beijing Institute of Technology》 EI CAS 2010年第1期66-70,共5页
A simple identification method based on a closed-loop experiment is proposed to measure the infinity norm of sensitivity function.A chirp signal,modified to have desired band-limited characteristic and finite duration... A simple identification method based on a closed-loop experiment is proposed to measure the infinity norm of sensitivity function.A chirp signal,modified to have desired band-limited characteristic and finite duration,is used as the excitation in the experiment,and the sensitivity function is calculated using Fourier transform of input and error signals before the infinity norm is evaluated through maximization of the magnitude of sensitivity function.With an additional feature of providing values of gain margin and phase margin at a little extra effort,this method can be used in the identification step of a controller auto-tuning procedure,as having been supported by simulation results showing its capability of providing fast and accurate estimates for a large variety of processes. 展开更多
关键词 sensitivity function CHIRP numerical optimization FFT AUTO-TUNING
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A Security Sensitive Function Mining Approach Based on Precondition Pattern Analysis
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作者 Zhongxu Yin Yiran Song +1 位作者 Huiqin Chen Yan Cao 《Computers, Materials & Continua》 SCIE EI 2020年第5期1013-1029,共17页
Security-sensitive functions are the basis for building a taint-style vulnerability model.Current approaches for extracting security-sensitive functions either don’t analyze data flow accurately,or not conducting pat... Security-sensitive functions are the basis for building a taint-style vulnerability model.Current approaches for extracting security-sensitive functions either don’t analyze data flow accurately,or not conducting pattern analyzing of conditions,resulting in higher false positive rate or false negative rate,which increased manual confirmation workload.In this paper,we propose a security sensitive function mining approach based on preconditon pattern analyzing.Firstly,we propose an enhanced system dependency graph analysis algorithm for precisely extracting the conditional statements which check the function parameters and conducting statistical analysis of the conditional statements for selecting candidate security sensitive functions of the target program.Then we adopt a precondition pattern mining method based on conditional statements nomalizing and clustering.Functions with fixed precondition patterns are regarded as security-sensitive functions.The experimental results on four popular open source codebases of different scales show that the approach proposed is effective in reducing the false positive rate and false negative rate for detecting security sensitive functions. 展开更多
关键词 Code mining security sensitive function function preconditions single-linkage clustering
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Visual perception alterations in COVID-19:a preliminary study 被引量:1
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作者 María Begoña Coco-Martín Luis Leal-Vega +6 位作者 Irene Alcoceba-Herrero Ainhoa Molina-Martín Dolores de-Fez María JoséLuque Carlos Dueñas-Gutiérrez Juan Francisco Arenillas-Lara David PPiñero 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第1期1-9,共9页
AIM:To compare the visual perception(color and chromatic-achromatic contrast vision)of a small cohort of COVID-19 patients at the time of infection and after 6mo with that of a healthy population matched for sex and a... AIM:To compare the visual perception(color and chromatic-achromatic contrast vision)of a small cohort of COVID-19 patients at the time of infection and after 6mo with that of a healthy population matched for sex and age.METHODS:A total of 25 patients(9 females,16 males,mean age:54±10y)with COVID-19 hospitalized in the COVID-19 Unit of the University Clinical Hospital of Valladolid were recruited for this preliminary study.Visual perception,as determined by monocular measurement of contrast sensitivity function(CSF)and color vision was assessed in each patient using the Optopad test.The results obtained were then compared with those of a sample of 16 age-and sex-matched healthy controls(5 females,11 males,mean age:50±6y)in which the same measurement procedure was repeated.Statistically significant differences between groups were assessed using the Mann-Whitney U test.Measurements were repeated after a minimum follow-up period of 6mo and statistically significant differences between the two time points in each group were assessed using the Wilcoxon signed rank test.RESULTS:Discrimination thresholds(color and chromatic-achromatic contrast vision)and their corresponding sensitivity,calculated as the inverse of the discrimination threshold,were evaluated.Analysis of the data revealed higher contrast threshold results(i.e.,worse contrast sensitivity)in the COVID-19 group than in the control group for all spatial frequencies studied in the Optopad-CSF achromatic test and most of the spatial frequencies studied in the Optopad-CSF chromatic test for the red-green and blue-yellow mechanisms.In addition,color threshold results in the COVID-19 group were also significantly higher(i.e.,worse color sensitivity)for almost all color mechanisms studied in the Optopad-Color test.At 6mo,most of the differences found between the groups were maintained despite COVID-19 recovery.CONCLUSION:The present results provide preliminary evidence that visual perception may be impaired in COVID-19,even when the infection has passed.Although further research is needed to determine the precise causes of this finding,analysis of CSF and color vision could provide valuable information on the visual impact of COVID-19. 展开更多
关键词 SARS-CoV-2 COVID-19 visual perception contrast sensitivity function color vision
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NEW VISUAL PERCEPTUAL POOLING STRATEGY FOR IMAGE QUALITY ASSESSMENT 被引量:2
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作者 Zhou Wujie Jiang Gangyi Yu Mei 《Journal of Electronics(China)》 2012年第3期254-261,共8页
Most of Image Quality Assessment (IQA) metrics consist of two processes. In the first process, quality map of image is measured locally. In the second process, the last quality score is converted from the quality map ... Most of Image Quality Assessment (IQA) metrics consist of two processes. In the first process, quality map of image is measured locally. In the second process, the last quality score is converted from the quality map by using the pooling strategy. The first process had been made effective and significant progresses, while the second process was always done in simple ways. In the second process of the pooling strategy, the optimal perceptual pooling weights should be determined and computed according to Human Visual System (HVS). Thus, a reliable spatial pooling mathematical model based on HVS is an important issue worthy of study. In this paper, a new Visual Perceptual Pooling Strategy (VPPS) for IQA is presented based on contrast sensitivity and luminance sensitivity of HVS. Experimental results with the LIVE database show that the visual perceptual weights, obtained by the proposed pooling strategy, can effectively and significantly improve the performances of the IQA metrics with Mean Structural SIMilarity (MSSIM) or Phase Quantization Code (PQC). It is confirmed that the proposed VPPS demonstrates promising results for improving the performances of existing IQA metrics. 展开更多
关键词 Image Quality Assessment (IQA) Visual Perceptual Pooling Strategy(VPPS) Contrast sensitivity function (CSF) Luminance sensitivity function (LSF)
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A NEW QUANTITATIVE WAY FOR DETERMINING LEAF AREA INDEX AND NET PRIMARY PRODUCTIVITY IN REGIONAL SCALE 被引量:7
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作者 Zhang Renhua(Institute of Geography, CAS, Bejing 100101, P.R. China)Andres Kuusk(Estorua Observatory, Tatu, Estorua)Chen Gang(Ground Station of Satellite Remote Sensing, CAS, Behing 100086, P.R. China)Alan Strahler Li Xiaonen(Remote Sensing Cater, Boston 《Journal of Geographical Sciences》 SCIE CSCD 1996年第4期1-17,共17页
An inversion of bidirectional reflection distribution fiJnedon (BRDF) wastested using NK Model and NOAA AVHRR datu. The test involVed sensitiveanalysis, optimum inversion selecting, ground simulated expenment, calibra... An inversion of bidirectional reflection distribution fiJnedon (BRDF) wastested using NK Model and NOAA AVHRR datu. The test involVed sensitiveanalysis, optimum inversion selecting, ground simulated expenment, calibrahngmeasuremed with satellite and computer image processmg. Results of comparisonwith NDVI indicatal that inversion of BRDF will have brigh developing prospect inthe next decade. 展开更多
关键词 leaf area index transmission coefficient inversion sensitivity bidirectional refectance distribution function
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Theoretical Calculation about the High Energy Density Molecules of Nitrate Ester Substitution Derivatives of Prismane 被引量:2
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作者 李步通 迟伟杰 李璐琳 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第8期1306-1312,共7页
The nitrate ester substitution derivatives of prismane were studied at the B3LYP/6-311G** level. The sublimation enthalpies and heats of formation in gas phase and solid state were calculated. The detonation perform... The nitrate ester substitution derivatives of prismane were studied at the B3LYP/6-311G** level. The sublimation enthalpies and heats of formation in gas phase and solid state were calculated. The detonation performances were also predicted by using the famous Kamlet-Jacbos equation. Our calculated results show that introducing nitrate ester group into prismane is helpful to enhance its detonation properties. Stabilities were evaluated through the bond dissociation energies, bond order, characteristic heights(H50) and band gap calculations. The trigger bonds in the pyrolysis process of prismane derivatives were confirmed as O–ON2 bond. The BDEs of all compounds were large, so these prismane derivatives have excellent stability consistent with the results of H50 and band gap. 展开更多
关键词 prismane nitrate ester group high energy density compounds impact sensitive density functional theory
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Photoelectric Property of Polyaniline Doped with Organic Sulphonic Acid 被引量:1
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作者 FENG Wei,WANG Hui, ZHENG Jian-bang, LI Cheng-quan,WEI Wei, WU Hong-cai (School of Electron. & Inform. Eng., Xi’an Jiaotong University, Xi’an 710049,CHN) 《Semiconductor Photonics and Technology》 CAS 1999年第2期119-124,共6页
Photoelectric property of polyaniline doped with dodecyl-benzene sulphonic acid (DBSA) is studied. The result shows that the concentration of carrier increases obviously, when polyaniline doped with DBSA is irradiated... Photoelectric property of polyaniline doped with dodecyl-benzene sulphonic acid (DBSA) is studied. The result shows that the concentration of carrier increases obviously, when polyaniline doped with DBSA is irradiated with light. Mixture of sensitive material is advantageous to the absorption of polyaniline in visible light spectrum, and the conductivity is also improved. The results of dielectric measurements on polyaniline doped with DBSA in an Al-PAn-DBSA-Al configuration as function of frequency and temperature are reported. The space-charge polarization phenomenon is observed. Carrier lifetime is microsecond magnitude and mobility is (0.001~0.1) cm 2/V·s, which are obtained by calculation or experiment. The active energy is obtained from the relation between conductivity and temperature. The conducting mechanism of PAn-DBSA is analyzed. 展开更多
关键词 Dielectric Relaxation Doping Photoelectric functional Material Polyaniline Sensitive Dye CLC number:O 631.23 O 632.7 TN304.52 Document code:A
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Numerical and physical simulations of array laterolog in deviated anisotropic formation
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作者 Yi-Zhi Wu Zhen-Guan Wu +3 位作者 Yi-Ren Fan Tao Xing Chao-Liu Li Chao Yuan 《Petroleum Science》 SCIE CAS CSCD 2022年第5期2107-2119,共13页
Due to the tremendous amount of high-resolution measurement information,array laterolog is widely used in evaluations of deviated anisotropic reservoirs.However,the precision of a complementary numerical simulation sh... Due to the tremendous amount of high-resolution measurement information,array laterolog is widely used in evaluations of deviated anisotropic reservoirs.However,the precision of a complementary numerical simulation should be improved as high as the core of fine-scale reservoir evaluation.Therefore,the 3D finite element method(3D-FEM)is presented to simulate the array laterolog responses.Notably,a downscaled physical simulation system is introduced to validate and calibrate the precision of the 3D-FEM.First,the size of the downscaled system is determined by COMSOL.Then,the surrounding and investigated beds are represented by a sodium chloride solution and planks soaked in solution,respectively.Finally,a half-space measurement scheme is presented to improve the experimental efficiency.Moreover,the corresponding sensitivity function and separation factor are established to analyze the effects of the formation anisotro py and dipping angle on the array laterolog responses.The numerical and experimental results indicate that the half-space method is practical,and the mean relative error between the numerical and experimental results is less than 5%,which indicates that the numerical simulation is accurate.With the proposed approach,the reversal angle of array laterolog response curves in anisotropic formations can be observed,and this range is determined to be 50°-62°. 展开更多
关键词 Anisotropic formation Array laterolog Downscaled physical simulation sensitivity function Reversal angle
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JPEG2000 COMPRESSION CODING USING HUMAN VISUAL SYSTEM MODEL
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作者 XiaoJiang WuChengke 《Journal of Electronics(China)》 2005年第1期53-58,共6页
In order to apply the Human Visual System (HVS) model to JPEG2000 standard,several implementation alternatives are discussed and a new scheme of visual optimization isintroduced with modifying the slope of rate-distor... In order to apply the Human Visual System (HVS) model to JPEG2000 standard,several implementation alternatives are discussed and a new scheme of visual optimization isintroduced with modifying the slope of rate-distortion. The novelty is that the method of visual weighting is not lifting the coefficients in wavelet domain, but is complemented by code stream organization. It remains all the features of Embedded Block Coding with Optimized Truncation (EBCOT) such as resolution progressive, good robust for error bit spread and compatibility of lossless compression. Well performed than other methods, it keeps the shortest standard codestream and decompression time and owns the ability of VIsual Progressive (VIP) coding. 展开更多
关键词 JPEG2000 Contrast sensitivity function(CSF) The rate-distortion slope Embedded coding Visual Progressive(VIP)
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THE DESIGN OF AN ALL-DIGITAL PHASE-LOCKED LOOP WITH LOW JITTER BASED ON ISF ANALYSIS
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作者 Deng Xiaoying Yang Jun Shi Longxing Chen Xin 《Journal of Electronics(China)》 2008年第5期673-678,共6页
A low jitter All-Digital Phase-Locked Loop (ADPLL) used as a clock generator is designed. The Digital-Controlled Oscillator (DCO) for this ADPLL is a seven-stage ring oscillator with the delay of each stage change... A low jitter All-Digital Phase-Locked Loop (ADPLL) used as a clock generator is designed. The Digital-Controlled Oscillator (DCO) for this ADPLL is a seven-stage ring oscillator with the delay of each stage changeable. Based on the Impulse Sensitivity Function (ISF) analysis, an effective way is proposed to reduce the ADPLL's jitter by the careful design of the sizes of the inverters used in the DCO with a simple architecture other than a complex one. The ADPLL is implemented in a 0.18μm CMOS process with 1.SV supply voltage, occupies 0.046mm^2 of on-chip area. According to the measured results, the ADPLL can operate from 108MHz to 304MHz, and the peak-to-peak jitter is 139ps when the DCO's output frequency is 188MHz. 展开更多
关键词 All-Digital Phase Locked Loop (ADPLL) Digital Controlled Oscillator (DCO) Impulse sensitivity function (ISF) Thermal noise JITTER
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Robust Control of Time Delay Systems
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作者 Farhati Samia Bel Hadj All Naoui Saloua Abdelkrim Mohamed Naceur 《Computer Technology and Application》 2012年第1期69-75,共7页
This study presents the design of both H∞ Loop Shaping Control (HLSC) and Internal Model Control (IMC) strategies for linear time delay systems. For first order time delay system, a systematic approach for weight... This study presents the design of both H∞ Loop Shaping Control (HLSC) and Internal Model Control (IMC) strategies for linear time delay systems. For first order time delay system, a systematic approach for weight selection based on the sensitivity function was proposed, then compared to the internal model control strategy. For both methods, the synthesis was based on the Pade approximation. Two cases are considered for time delay: upper or lower than system time constant. Simulation results for the proposed approaches are acceptable ever in presence of disturbances and model mismatches. 展开更多
关键词 H∞ loop shaping control internal model control sensitivity function constant delay Pade approximation model mismatches.
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Comparison of ocular modulation transfer function determined by a ray-tracing aberrometer and a double-pass system in early cataract patients 被引量:3
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作者 Qiao Liya Wan Xiuhua +6 位作者 Cai Xiaogu Balamurali Vasudevan Xiong Ying Tan Jiaxuan Guan Zheng David A Atchison Wang Ningli 《Chinese Medical Journal》 SCIE CAS CSCD 2014年第19期3454-3458,共5页
Background The evaluation of retinal image quality in cataract eyes has gained importance and the clinical modulation transfer functions (MTF) can obtained by aberrometer and double pass (DP) system. This study ai... Background The evaluation of retinal image quality in cataract eyes has gained importance and the clinical modulation transfer functions (MTF) can obtained by aberrometer and double pass (DP) system. This study aimed to compare MTF derived from a ray tracing aberrometer and a DP system in early cataractous and normal eyes. Methods There were 128 subjects with 61 control eyes and 67 eyes with early cataract defined according to the Lens Opacities Classification System II1. A laser ray-tracing wavefront aberrometer (iTrace) and a double pass (DP) system (OQAS) assessed ocular MTF for 6.0 mm pupil diameters following dilation. Areas under the MTF (AUMTF) and their correlations were analyzed. Stepwise multiple regression analysis assessed factors affecting the differences between iTrace- and OQAS-derived AUMTF for the early cataract group. Results For both early cataract and control groups, iTrace-derived MTFs were higher than OQAS-derived MTFs across a range of spatial frequencies (P 〈0.01). No significant difference between the two groups occurred for iTrace-derived AUMTF, but the early cataract group had significantly smaller OQAS-derived AUMTF than did the control group (P 〈0.01). AUMTF determined from both the techniques demonstrated significant correlations with nuclear opacities, higher-order aberrations (HOAs), visual acuity, and contrast sensitivity functions, while the OQAS-derived AUMTF also demonstrated significant correlations with age and cortical opacity grade. The factors significantly affecting the difference between iTrace and OQAS AUMTF were root-mean-squared HOAs (standardized beta coefficient=-0.63, P 〈0.01) and age (standardized beta coefficient=0.26, P 〈0.01). Conclusions MTFs determined from a iTrace and a DP system (OQAS) differ significantly in early cataractous and normal subjects. Correlations with visual performance were higher for the DP system. OQAS-derived MTF may be useful as an indicator of visual performance in early cataract eyes. 展开更多
关键词 CATARACT contrast sensitivity function double-pass system modulation transfer function retinal image quality wavefront aberration
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Avian contrast sensitivity inspired contour detector for unmanned aerial vehicle landing 被引量:2
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作者 DENG YiMin DUAN HaiBin 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2017年第12期1958-1965,共8页
Runway detection is a demanding task for autonomous landing of unmanned aerial vehicles. Inspired by the attenuation effect and surround suppression mechanism, a novel biologically computational method based on the av... Runway detection is a demanding task for autonomous landing of unmanned aerial vehicles. Inspired by the attenuation effect and surround suppression mechanism, a novel biologically computational method based on the avian contrast sensitivity is proposed for runway contour detection. For the noisy stimuli, deniosed responses of the biologically inspired Gabor energy operator are generalized followed by the denoising layer and the multiresolution fusion layer. Moreover, two factors such as contour effect and texture suppression are considered in the contrast sensitivity based surround inhibition. Different from traditional detectors, which do not distinguish between contours and texture edges, the proposed method can respond strongly to contours and suppress the texture information. Applying the contrast sensitivity inspired detector to noisy runway scenes yields effective contours, while the non-meaningful texture elements are removed dramatically at the same time. Besides the superior performance over traditional detectors, the proposed method is capable to provide insight into the attenuation effect of the avian contrast sensitivity function and has potential applications in computer vision and pattern recognition. 展开更多
关键词 contrast sensitivity function surround suppression contour perception unmanned aerial vehicle landing
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Regional moment-independent sensitivity analysis with its applications in engineering 被引量:8
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作者 Changcong ZHOU Chenghu TANG +2 位作者 Fuchao LIU Wenxuan WANG Zhufeng YUE 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第3期1031-1042,共12页
Traditional Global Sensitivity Analysis(GSA) focuses on ranking inputs according to their contributions to the output uncertainty.However,information about how the specific regions inside an input affect the output ... Traditional Global Sensitivity Analysis(GSA) focuses on ranking inputs according to their contributions to the output uncertainty.However,information about how the specific regions inside an input affect the output is beyond the traditional GSA techniques.To fully address this issue,in this work,two regional moment-independent importance measures,Regional Importance Measure based on Probability Density Function(RIMPDF) and Regional Importance Measure based on Cumulative Distribution Function(RIMCDF),are introduced to find out the contributions of specific regions of an input to the whole output distribution.The two regional importance measures prove to be reasonable supplements of the traditional GSA techniques.The ideas of RIMPDF and RIMCDF are applied in two engineering examples to demonstrate that the regional moment-independent importance analysis can add more information concerning the contributions of model inputs. 展开更多
关键词 Cumulative distribution function Moment-independent Probability density function Regional importance measure sensitivity analysis Uncertainty
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