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What is the Most Effective Method of Error Correction in L2 Writing? 被引量:2
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作者 顾红兵 《海外英语》 2011年第10X期37-39,共3页
The efficacy of error correction and various kinds of correction approaches is one of the key issues in second language writing faced by both teachers and researchers. The current paper reviews the definition of error... The efficacy of error correction and various kinds of correction approaches is one of the key issues in second language writing faced by both teachers and researchers. The current paper reviews the definition of error correction and examines the different views on whether error correction in L2 writing should be corrected. In particular, the paper discusses and analyses the three common correction methods: direct correction, peer feedback and indirect correction. Teachers are encouraged to weigh and analyze the advantages and disadvantages of these methods according to the current literature, employ the most beneficial error correction method in L2 writing, and adapt its suitability to their teaching context. 展开更多
关键词 error CORRECTION L2 WRITING effective method
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Effect of Modulation Error on All Optical Fiber Current Transformers 被引量:3
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作者 Zhengping Wang Yuekun Wang Shuai Sun 《Journal of Sensor Technology》 2012年第4期172-176,共5页
For actively modulated In-line Sagnac interferential all optic fiber current transformers (AOFCTs), the accuracies are directly affected by the amplitude of the modulation signal. In order to deeply undertand the func... For actively modulated In-line Sagnac interferential all optic fiber current transformers (AOFCTs), the accuracies are directly affected by the amplitude of the modulation signal. In order to deeply undertand the function of the modulator, a theoretical model of modulation effect to AOFCTs is built up in this paper. The effect of the amplitude of the modulation signal to the output intensity of AOFCTs is theoretically formulated and numerical calculated. The results show that the modulation voltage variation could affect the output accuracies significantly. This might be some references on the investigation for practical applications of AOFCTs. 展开更多
关键词 Electronic CURRENT TRANSFORMER All Optical FIBER CURRENT TRANSFORMER Faraday effect Active MODULATION MODULATION error
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ADC border effect and suppression of quantization error in the digital dynamic measurement 被引量:3
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作者 白丽娜 刘海东 +7 位作者 周渭 张勇 翟鸿启 崔震健 赵明英 谷小倩 刘蓓玲 黄李贝 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第9期91-97,共7页
The digital measurement and processing is an important direction in the measurement and control field. The quantization error widely existing in the digital processing is always the decisive factor that restricts the ... The digital measurement and processing is an important direction in the measurement and control field. The quantization error widely existing in the digital processing is always the decisive factor that restricts the development and applications of the digital technology. In this paper, we find that the stability of the digital quantization system is obviously better than the quantization resolution. The application of a border effect in the digital quantization can greatly improve the accuracy of digital processing. Its effective precision has nothing to do with the number of quantization bits, which is only related to the stability of the quantization system. The high precision measurement results obtained in the low level quantization system with high sampling rate have an important application value for the progress in the digital measurement and processing field. 展开更多
关键词 quantization error border effect digital converter(ADC)
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Practice and Effect of Appropriate Error-correction in English Teaching 被引量:2
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作者 任静明 胡蓉 《Journal of Donghua University(English Edition)》 EI CAS 2002年第2期140-142,共3页
This paper points out that with interference from their native language and culture, Chinese students will inevitably make some errors in the process of learning English. It is important for teachers to know when and ... This paper points out that with interference from their native language and culture, Chinese students will inevitably make some errors in the process of learning English. It is important for teachers to know when and how to correct the students’ errors. By employing error-correction skillfully and appropriately, one can expect to improve the present English teaching and learning, to develop the self-confidence and self-esteem in students themselves. 展开更多
关键词 error-correction practice effect
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Introduction of New Method on Engineering Risk Assessment:Engineering Errors and Effects Analysis(3EA)
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作者 Mohammad Mahdi Izadi 《Management Studies》 2018年第6期527-530,共4页
Construction and commissioning accidents investigation shows that engineer’s errors in basic and detailed phases are the main causes.It will be gained more efficiency of investment when a relevant method is applied f... Construction and commissioning accidents investigation shows that engineer’s errors in basic and detailed phases are the main causes.It will be gained more efficiency of investment when a relevant method is applied for error identification and risk assessment in basic and detailed phases.Most of risk assessment methods are related to construction phase,meanwhile hidden risks that were happen in previous phases cannot be found by these methods.Although HAZOP study can be applied in detail phase but it can help to find process defections.Importance of identifying risks in basic and detailed phases is to apply preventive actions against birth and grows risks.This risk assessment method can reduce costs and improve environmental protection,safety,and reliability of designs.The main purpose of this study is to identify engineer’s errors and analyse their HSE effects.The method is applied in seven oil and gas engineering projects in Iran,raising the level of engineer’s attention to safety precautions and environmentally-friendly design,reducing the cost of improving the level of safety and environmental protection,improving environmental protection,safety,and design reliability,and improving procedures related to design process and control have been achieved. 展开更多
关键词 ENGINEERING errorS and effectS Analysis(3EA) ENGINEERING error detailed effectIVENESS control risk assessment
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Warburg effect mimicking inborn errors of metabolism in childhood hematologic malignancies:A case-based systematic review
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作者 Khanittha Permtawee Maliwan Tengsujaritkul +5 位作者 Chane Choed-Amphai Supapitch Chanthong Kanittha Mankhemthong Lalita Sathitsamitphong Rungrote Natesirinilkul Pimlak Charoenkwan 《World Journal of Clinical Pediatrics》 2023年第5期350-358,共9页
BACKGROUND Type B lactic acidosis and hypoglycemia can occur in various pediatric conditions.In young children with a history of fasting preceding these metabolic derangements,inborn errors of metabolism should be pri... BACKGROUND Type B lactic acidosis and hypoglycemia can occur in various pediatric conditions.In young children with a history of fasting preceding these metabolic derangements,inborn errors of metabolism should be primarily considered.However,the Warburg effect,a rare metabolic complication,can also manifest in children with hematologic malignancies.Only a few reports of this condition in children have been published in the literature.AIM To identify the clinical course,treatment strategies,and outcomes of childhood hematologic malignancies with type B lactic acidosis.METHODS We performed a comprehensive search of the PubMed,Scopus,and Cochrane databases without any time restriction but limited to English language articles.The databases were last accessed on July 1st,2023.RESULTS A total of 20 publications were included in the analysis,all of which were case reports or case series.No higher quality evidence was available.Among children with hematologic malignancies and Warburg effect,there were 14 cases of acute lymphoblastic leukemia and 6 cases of non-Hodgkin’s lymphoma including our illustrative case.Lactic acidosis occurred in 55%of newly diagnosed cases and 45%of relapsed cases.The mean age was 10.3±4.5 years,and 80%of cases were male.The mean serum lactate was 16.9±12.6 mmol/L,and 43.8%of the cases had concomitant hypoglycemia.Lactic acidosis initially subsided in 80%of patients receiving chemotherapy compared to 60%in the contrast group.The mortality rate of newly diagnosed cases was 45.5%,while the relapsed cases represented a 100%mortality rate.All 8 patients reported before 2001 died from disease-related complications.However,patients described in reports published between 2003 and 2023 had a 54.5%rate of complete remission.CONCLUSION This complication has historically led to fatal outcome;however,patients who received chemotherapy showed a more favorable response.Therefore,it is crucial to promptly initiate specific treatment in this context. 展开更多
关键词 Warburg effect Lactic acidosis type B Inborn errors of metabolism LEUKEMIA LYMPHOMA CHILDREN
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Effect of Healthcare Failure Mode and Effect Analysis on Reducing Error Risk of Neonatal Parenteral Nutrition Solution Dispensing
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作者 Xinhong ZHAO Zhenhua LIU +3 位作者 Chao SUN Xu XIAO Lixue ZHAO Chunhua CAI 《Medicinal Plant》 CAS 2022年第2期63-69,共7页
[Objectives]To investigate the effect of healthcare failure mode and effect analysis(HFMEA)on reducing error risk of neonatal parenteral nutrition solution dispensing.[Methods]A research team was established to identi... [Objectives]To investigate the effect of healthcare failure mode and effect analysis(HFMEA)on reducing error risk of neonatal parenteral nutrition solution dispensing.[Methods]A research team was established to identify the failure mode(FM)in each link of the formulation process of neonatal parenteral nutrition solution by HFMEA,quantify the severity(S),occurrence(O)and detection(D)of FM,and evaluate FM by risk priority number(RPN).For FM with the values of RPN>16,failure cause analysis was conducted,and corresponding improvement measures were formulated.The weight coefficient and random consistency ratio(CR)of deployment process were calculated in Matlab R2018a by compiling the Analytic Hierarchy Process(AHP)program.Six months after the implementation of improvement measures,the implementation effect was evaluated by comparing the changes of the values of RPN which was evaluated comprehensively and the rate of dispensing errors before and after the implementation of HFMEA.[Results]In the preparation process of neonatal parenteral nutrition solution,a total of 13 FMs with medium and above risk were found,the weight coefficient of medical order review,dosing and mixing was 0.2703,the weight coefficient of drug dispensing check and review was 0.1432,the weight coefficient of print label was 0.1015,the weight coefficient of distribution was 0.0716,and CR=0.0491<0.1.After six months of intervention,the total RPN value decreased by 64.81%from 127.8 to 45.0.The deployment error rates were significantly lower after the implementation,and the difference was statistically significant(P<0.05).[Conclusions]HFMEA can effectively reduce the error risk in preparation of neonatal parenteral nutrition solution,improve the quality of dispensing and promote the safety of neonatal medication. 展开更多
关键词 Healthcare failure mode and effect analysis(HFMEA) Neonatal parenteral nutrition solution Dispensing errors Risk management Analytic hierarchy process(AHP)
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Error Analysis of CET-4 Translation Produced by Vocational & Techni⁃ cal College Students and the Backwash Effect of English Teaching
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作者 马理明 《海外英语》 2020年第24期150-151,共2页
CET-4 is a national standardized English proficiency test designed and developed by the National College English Ex⁃amination Committee.The purpose of the test is to accurately measure the comprehensive English applic... CET-4 is a national standardized English proficiency test designed and developed by the National College English Ex⁃amination Committee.The purpose of the test is to accurately measure the comprehensive English application ability of college stu⁃dents in China.The more important the test,the more obvious its backwash effect.With the increase of the proportion of subjective questions in CET-4,teachers should pay more attention to the transfer of skills and correct English expression while teaching the basic knowledge of English.In particular,the students in vocational and technical colleges are weak in English abilities,and their errors in translation are even more numerous and varied.Therefore,this study will analyze the translation errors produced by 200 vocational and technical college students in CET-4 of June 2019.By interviewing and investigating the students’actual situation of English learning,tips and proposals on backwash effect on teaching can be achieved. 展开更多
关键词 vocational&technical college students CET-4 translation error analysis backwash effect on teaching
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Effectiveness and failure modes of error correcting code in industrial 65 nm CMOS SRAMs exposed to heavy ions
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作者 童腾 王晓辉 +4 位作者 张战刚 丁朋程 刘杰 刘天奇 苏弘 《Nuclear Science and Techniques》 SCIE CAS CSCD 2014年第1期47-52,共6页
Single event upsets(SEUs) induced by heavy ions were observed in 65 nm SRAMs to quantitatively evaluate the applicability and effectiveness of single-bit error correcting code(ECC) utilizing Hamming Code.The results s... Single event upsets(SEUs) induced by heavy ions were observed in 65 nm SRAMs to quantitatively evaluate the applicability and effectiveness of single-bit error correcting code(ECC) utilizing Hamming Code.The results show that the ECC did improve the performance dramatically,with the SEU cross sections of SRAMs with ECC being at the order of 10^(-11) cm^2/bit,two orders of magnitude higher than that without ECC(at the order of 10^(-9) cm^2/bit).Also,ineffectiveness of ECC module,including 1-,2- and 3-bits errors in single word(not Multiple Bit Upsets),was detected.The ECC modules in SRAMs utilizing(12,8) Hamming code would lose work when 2-bits upset accumulates in one codeword.Finally,the probabilities of failure modes involving 1-,2- and 3-bits errors,were calcaulated at 39.39%,37.88%and 22.73%,respectively,which agree well with the experimental results. 展开更多
关键词 SRAM 重离子 CMOS 故障模式 纳米 纠错码 工业 ECC
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基于立式850的数控机床几何误差分析与补偿模型研究
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作者 许小娟 《科学技术创新》 2026年第4期29-32,共4页
本研究以立式850数控机床为研究对象,系统开展几何误差分析与补偿模型研究。首先通过激光干涉仪对机床X、Y、Z轴几何误差进行精准测量,然后利用MATLAB软件完成多项式最小二乘拟合,最后建立了各轴定位误差与直线度误差的数学模型,并经残... 本研究以立式850数控机床为研究对象,系统开展几何误差分析与补偿模型研究。首先通过激光干涉仪对机床X、Y、Z轴几何误差进行精准测量,然后利用MATLAB软件完成多项式最小二乘拟合,最后建立了各轴定位误差与直线度误差的数学模型,并经残差分析验证了模型的高精度,为提高立式850数控机床加工精度提供理论与技术支持。 展开更多
关键词 数控机床 几何误差 有效补偿
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基于改进YOLOv8m的道路目标检测算法 被引量:1
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作者 孙虎成 臧可 吕晓晓 《电子设计工程》 2026年第2期12-18,25,共8页
对道路目标的准确检测是保证自动驾驶车辆安全行驶的一项关键技术。针对图像中被遮挡目标和远距离目标存在的特征模糊问题,提出一种改进型YOLOv8m的道路目标检测算法。该文在YOLOv8m的基础上引入可变形卷积,提高模型捕获目标实际边界的... 对道路目标的准确检测是保证自动驾驶车辆安全行驶的一项关键技术。针对图像中被遮挡目标和远距离目标存在的特征模糊问题,提出一种改进型YOLOv8m的道路目标检测算法。该文在YOLOv8m的基础上引入可变形卷积,提高模型捕获目标实际边界的能力;同时引入双层路由注意力机制,以稀疏感知的方式使模型聚焦于图像中的关键目标区域;此外构造小目标检测层,提升模型对远距离小目标的检出能力,并针对误差放大效应对模型推理性能造成的影响,设计分阶段学习策略稳定模型训练过程。基于KITTI数据集和Waymo数据集的实验结果显示,所提算法的mAP50相较于基准模型分别提高了4.6%和4.9%,有效提升了道路目标检测的精度。 展开更多
关键词 目标检测 YOLOv8m 目标遮挡 注意力机制 误差放大效应
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Heavy-ion and pulsed-laser single event effects in 130-nm CMOS-based thin/thick gate oxide anti-fuse PROMs 被引量:9
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作者 Chang Cai Tian-Qi Liu +8 位作者 Xiao-Yuan Li Jie Liu Zhan-Gang Zhang Chao Geng Pei-Xiong Zhao Dong-Qing Li Bing Ye Qing-Gang Ji Li-Hua Mo 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第5期92-102,共11页
Single event effects of 1-T structure programmable read-only memory(PROM) devices fabricated with a 130-nm complementary metal oxide semiconductorbased thin/thick gate oxide anti-fuse process were investigated using h... Single event effects of 1-T structure programmable read-only memory(PROM) devices fabricated with a 130-nm complementary metal oxide semiconductorbased thin/thick gate oxide anti-fuse process were investigated using heavy ions and a picosecond pulsed laser. The cross sections of a single event upset(SEU) for radiationhardened PROMs were measured using a linear energy transfer(LET) ranging from 9.2 to 95.6 MeV cm^2mg^(-1).The result indicated that the LET threshold for a dynamic bit upset was ~ 9 MeV cm^2mg^(-1), which was lower than the threshold of ~ 20 MeV cm^2mg^(-1) for an address counter upset owing to the additional triple modular redundancy structure present in the latch. In addition, a slight hard error was observed in the anti-fuse structure when employing209 Bi ions with extremely high LET values(~ 91.6 MeV cm^2mg^(-1)) and large ion fluence(~ 1×10~8 ions cm^(-2)). To identify the detailed sensitive position of a SEU in PROMs, a pulsed laser with a 5-μm beam spot was used to scan the entire surface of the device.This revealed that the upset occurred in the peripheral circuits of the internal power source and I/O pairs rather than in the internal latches and buffers. This was subsequently confirmed by a ^(181)Ta experiment. Based on the experimental data and a rectangular parallelepiped model of the sensitive volume, the space error rates for the used PROMs were calculated using the CRèME-96 prediction tool. The results showed that this type of PROM was suitable for specific space applications, even in the geosynchronous orbit. 展开更多
关键词 Anti-fuse PROM Single event effects HEAVY ions PULSED laser Space error rate
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Residual lifetime prediction model of nonlinear accelerated degradation data with measurement error 被引量:12
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作者 Zhongyi Cai Yunxiang Chen +1 位作者 Qiang Zhang Huachun Xiang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第5期1028-1038,共11页
For the product degradation process with random effect (RE), measurement error (ME) and nonlinearity in step-stress accelerated degradation test (SSADT), the nonlinear Wiener based degradation model with RE and ME is ... For the product degradation process with random effect (RE), measurement error (ME) and nonlinearity in step-stress accelerated degradation test (SSADT), the nonlinear Wiener based degradation model with RE and ME is built. An analytical approximation to the probability density function (PDF) of the product's lifetime is derived in a closed form. The process and data of SSADT are analyzed to obtain the relation model of the observed data under each accelerated stress. The likelihood function for the population-based observed data is constructed. The population-based model parameters and its random coefficient prior values are estimated. According to the newly observed data of the target product in SSADT, an analytical approximation to the PDF of its residual lifetime (RL) is derived in accordance with its individual degradation characteristics. The parameter updating method based on Bayesian inference is applied to obtain the posterior value of random coefficient of the RL model. A numerical example by simulation is analyzed to verify the accuracy and advantage of the proposed model. 展开更多
关键词 accelerated degradation test residual lifetime (RL) prediction measurement error random effect NONLINEARITY
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Prediction of proton-induced SEE error rates for the VATA160 ASIC 被引量:1
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作者 Kai Xi Di Jiang +7 位作者 Shan-Shan Gao Jie Kong Hong-Yun Zhao Hai-Bo Yang Tian-Qi Liu Bin Wang Bing Ye Jie Liu 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第1期88-93,共6页
We predict proton single event effect(SEE)error rates for the VATA160 ASIC chip on the Dark Matter Particle Explorer(DAMPE) to evaluate its radiation tolerance.Lacking proton test facilities,we built a Monte Carlo sim... We predict proton single event effect(SEE)error rates for the VATA160 ASIC chip on the Dark Matter Particle Explorer(DAMPE) to evaluate its radiation tolerance.Lacking proton test facilities,we built a Monte Carlo simulation tool named PRESTAGE to calculate the proton SEE cross-sections.PRESTAGE is based on the particle transport toolkit Geant4.It adopts a location-dependent strategy to derive the SEE sensitivity of the device from heavy-ion test data,which have been measured at the HI-13 tandem accelerator of the China Institute of Atomic Energy and the heavy-ion research facility in Lanzhou.The AP-8,SOLPRO,and August 1972 worst-case models are used to predict the average and peak proton fluxes on the DAMPE orbit.Calculation results show that the averaged proton SEE error rate for the VATA160 chip is approximately 2.17×10^(-5)/device/day.Worst-case error rates for the Van Allen belts and solar energetic particle events are 1-3 orders of magnitude higher than the averaged error rate. 展开更多
关键词 PROTON ASIC SINGLE EVENT effects error rates
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Mathematical Statistics Method of Evaluating Application Effects of a New Type of Gas Anchor 被引量:1
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作者 Jun Wang Wen-He Li Rong Zhong 《Energy and Power Engineering》 2015年第7期319-322,共4页
Based on the basic formula of the confidence interval and the sampling error of mathematical statistics, the mathematical statistics method of evaluating application effects of a new type of gas anchor was given in th... Based on the basic formula of the confidence interval and the sampling error of mathematical statistics, the mathematical statistics method of evaluating application effects of a new type of gas anchor was given in this paper. By the method mentioned above, the confidence interval and the sampling errors of the relevant mean value differences of Daqing Oilfield S block’s 150 wells, according to the mean value differences of the liquid producing capacity per day, the oil production per day, the submergence depth of the 10 sampling test wells, in which before and after a new type of gas anchor were laid down, were calculated. The calculation results show that a new type of gas anchor has a better effect of increasing oil production of oil well and enhancing pump efficiency. Through the real value differences analysis of the liquid producing capacity per day, the oil production per day, the submergence depth of 150 wells mentioned above, in which before and after a new type of gas anchor were laid down, it was verified. By using the confidence interval and the sampling errors of the liquid producing capacity per day, the oil production per day, the submergence depth mentioned above, in which before and after a new type of gas anchor were laid down, the application effects of a new type of gas anchor could be evaluated. And a mathematical statistics method of evaluation application effects of a new type of gas anchor is presented. 展开更多
关键词 A New Type of Gas ANCHOR CONFIDENCE INTERVAL Sampling error Application effects Evaluation
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Moving Least Squares Interpolation Based A-Posteriori Error Technique in Finite Element Elastic Analysis 被引量:1
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作者 Mohd Ahmed Devender Singh +1 位作者 Saeed Al Qadhi Nguyen Viet Thanh 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第10期167-189,共23页
The performance of a-posteriori error methodology based on moving least squares(MLS)interpolation is explored in this paper by varying the finite element error recovery parameters,namely recovery points and field vari... The performance of a-posteriori error methodology based on moving least squares(MLS)interpolation is explored in this paper by varying the finite element error recovery parameters,namely recovery points and field variable derivatives recovery.The MLS interpolation based recovery technique uses the weighted least squares method on top of the finite element method’s field variable derivatives solution to build a continuous field variable derivatives approximation.The boundary of the node support(mesh free patch of influenced nodes within a determined distance)is taken as circular,i.e.,circular support domain constructed using radial weights is considered.The field variable derivatives(stress and strains)are recovered at two kinds of points in the support domain,i.e.,Gauss points(super-convergent stress locations)and nodal points.The errors are computed as the difference between the stress from the finite element results and projected stress from the post-processed energy norm at both elemental and global levels.The benchmark numerical tests using quadrilateral and triangular meshes measure the finite element errors in strain and stress fields.The numerical examples showed the support domain-based recovery technique’s capabilities for effective and efficient error estimation in the finite element analysis of elastic problems.The MLS interpolation based recovery technique performs better for stress extraction at Gauss points with the quadrilateral discretization of the problem domain.It is also shown that the behavior of the MLS interpolation based a-posteriori error technique in stress extraction is comparable to classical Zienkiewicz-Zhu(ZZ)a-posteriori error technique. 展开更多
关键词 Recovery points field variable derivatives effectivity error recovery support domain error convergence
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The Synthetic Effect of Magnetorheological Finishing Technology:Analysis,Modeling,and Control 被引量:1
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作者 李蓓智 李中会 +2 位作者 杨建国 吴珊珊 陶晓峰 《Journal of Donghua University(English Edition)》 EI CAS 2010年第6期806-812,共7页
The controllable key factors in magnetorheological finishing device were studied to determine their influence on efficiency of magnetorheological finishing(MRF)and surface of MRF,as well as interaction between efficie... The controllable key factors in magnetorheological finishing device were studied to determine their influence on efficiency of magnetorheological finishing(MRF)and surface of MRF,as well as interaction between efficiency and surface.Based on theoretical and experimental research,the law of material removal was explored and a new process variable based material removal model(PVMR)was proposed.The experimental findings demonstrate that PVMR reveals the law of the material removal with introduction of three concepts and makes a material removal function z(y i)where the magnetorheological finishing process parameters are considered since they are easy to control and adjust.So the material function of this model is quadratic curve function which is readily suitable for stability and online control magnetorheological finishing. 展开更多
关键词 magnetorheological finishing quality control synthetical error effect analysis
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An Empirical Study of Downstream Analysis Effects of Model Pre-Processing Choices 被引量:1
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作者 Jessica M. Rudd Herman “Gene” Ray 《Open Journal of Statistics》 2020年第5期735-809,共75页
This study uses <span style="font-family:Verdana;">an empirical</span><span style="font-family:Verdana;"> analysis to quantify the downstream analysis effects of data pre-processi... This study uses <span style="font-family:Verdana;">an empirical</span><span style="font-family:Verdana;"> analysis to quantify the downstream analysis effects of data pre-processing choices. Bootstrap data simulation is used to measure the bias-variance decomposition of an empirical risk function, mean square error (MSE). Results of the risk function decomposition are used to measure the effects of model development choices on </span><span style="font-family:Verdana;">model</span><span style="font-family:Verdana;"> bias, variance, and irreducible error. Measurements of bias and variance are then applied as diagnostic procedures for model pre-processing and development. Best performing model-normalization-data structure combinations were found to illustrate the downstream analysis effects of these model development choices. </span><span style="font-family:Verdana;">In addition</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;">, results found from simulations were verified and expanded to include additional data characteristics (imbalanced, sparse) by testing on benchmark datasets available from the UCI Machine Learning Library. Normalization results on benchmark data were consistent with those found using simulations, while also illustrating that more complex and/or non-linear models provide better performance on datasets with additional complexities. Finally, applying the findings from simulation experiments to previously tested applications led to equivalent or improved results with less model development overhead and processing time.</span> 展开更多
关键词 Empirical Analysis Bias-Variance Decomposition Mean Squared error Downstream Analysis effects Empirical Risk
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Characteristics of Multipath Effects in GPS Dynamic Deformation Monitoring
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作者 HUANG Shengxiang JIN Xiangsheng YANG Baocen 《Geo-Spatial Information Science》 2006年第2期79-83,共5页
ABSTRACT The multipath has long been considered a major error source in GPS applications .The characteristics 0f the GPS signal multipath effects are analyzed. based on which an experiment that considers the characte... ABSTRACT The multipath has long been considered a major error source in GPS applications .The characteristics 0f the GPS signal multipath effects are analyzed. based on which an experiment that considers the characteristics of dynamic deformation monitoring has been carried out. The solution results of observation data in two successive days are processed by a method,which combines the wavelet filtering and the differential correction betweentwo successive days. The research demonstrates that the multipath errors have stronger repeatability on successive days;after significantly mitigating the influence of multipath effects,the accuracy of three-dimensional positioning for GPS dynamic deformation monitoring can attain the mm level,an obvious accuracy improving particularly invertical component.The characteristics of GPS signal multipath,th eexperimental scheme and the qualitative and quantitative analysis of results are detailed. 展开更多
关键词 GPS dynamic deformation monitoring multipath effects error characteristic
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Interval of effective time-step size for the numerical computation of nonlinear ordinary differential equations
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作者 CAO Jing LI Jian-Ping ZHANG Xin-Yuan 《Atmospheric and Oceanic Science Letters》 CSCD 2017年第1期17-20,共4页
The computational uncertainty principle states that the numerical computation of nonlinear ordinary differential equations(ODEs) should use appropriately sized time steps to obtain reliable solutions.However,the int... The computational uncertainty principle states that the numerical computation of nonlinear ordinary differential equations(ODEs) should use appropriately sized time steps to obtain reliable solutions.However,the interval of effective step size(IES) has not been thoroughly explored theoretically.In this paper,by using a general estimation for the total error of the numerical solutions of ODEs,a method is proposed for determining an approximate IES by translating the functions for truncation and rounding errors.It also illustrates this process with an example.Moreover,the relationship between the IES and its approximation is found,and the relative error of the approximation with respect to the IES is given.In addition,variation in the IES with increasing integration time is studied,which can provide an explanation for the observed numerical results.The findings contribute to computational step-size choice for reliable numerical solutions. 展开更多
关键词 Ordinary differential equations interval of effective step size computational uncertainty principle integration time relative error
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