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An Empirical Study of Chinese English Learners' Attitudes toward Errors and Error Correction in Question-asking
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作者 何周春 龚彦知 《海外英语》 2013年第24期310-312,共3页
Based on the questionnaire, this study found that :1) Elementary learners were inclined to commit more global errors compared to their local errors, whilst advanced learners make more local errors; 2) Interlingual fac... Based on the questionnaire, this study found that :1) Elementary learners were inclined to commit more global errors compared to their local errors, whilst advanced learners make more local errors; 2) Interlingual factors were more influential than intralingual factors in elementary learners' error making, but for advanced learners, intralingual factors played relatively a much more important role in error making; 3) Elementary learners preferred explicit correction whilst advanced learners favoured im?plicit correction in question-asking. 展开更多
关键词 errors error correction learning STAGES language p
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Single Photon Detection Technology in Underwater Wireless Optical Communication:Modulation Modes and Error Correction Coding Analysis
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作者 GAI Lei LI Wendong WANG Guoyu 《Journal of Ocean University of China》 CAS CSCD 2024年第2期405-414,共10页
This study explores the application of single photon detection(SPD)technology in underwater wireless optical communication(UWOC)and analyzes the influence of different modulation modes and error correction coding type... This study explores the application of single photon detection(SPD)technology in underwater wireless optical communication(UWOC)and analyzes the influence of different modulation modes and error correction coding types on communication performance.The study investigates the impact of on-off keying(OOK)and 2-pulse-position modulation(2-PPM)on the bit error rate(BER)in single-channel intensity and polarization multiplexing.Furthermore,it compares the error correction performance of low-density parity check(LDPC)and Reed-Solomon(RS)codes across different error correction coding types.The effects of unscattered photon ratio and depolarization ratio on BER are also verified.Finally,a UWOC system based on SPD is constructed,achieving 14.58 Mbps with polarization OOK multiplexing modulation and 4.37 Mbps with polarization 2-PPM multiplexing modulation using LDPC code error correction. 展开更多
关键词 error correction coding modulation mode single photon detection underwater communication wireless optical communication
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Errors and Correction of Precipitation Measurements in China 被引量:10
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作者 任芝花 黎明琴 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第3期449-458,共10页
In order to discover the range of various errors in Chinese precipitation measurements and seek a correction method, 30 precipitation evaluation stations were set up countrywide before 1993. All the stations are refer... In order to discover the range of various errors in Chinese precipitation measurements and seek a correction method, 30 precipitation evaluation stations were set up countrywide before 1993. All the stations are reference stations in China. To seek a correction method for wind-induced error, a precipitation correction instrument called the "horizontal precipitation gauge" was devised beforehand. Field intercomparison observations regarding 29,000 precipitation events have been conducted using one pit gauge, two elevated operational gauges and one horizontal gauge at the above 30 stations. The range of precipitation measurement errors in China is obtained by analysis of intercomparison measurement results. The distribution of random errors and systematic errors in precipitation measurements are studied in this paper. A correction method, especially for wind-induced errors, is developed. The results prove that a correlation of power function exists between the precipitation amount caught by the horizontal gauge and the absolute difference of observations implemented by the operational gauge and pit gauge. The correlation coefficient is 0.99. For operational observations, precipitation correction can be carried out only by parallel observation with a horizontal precipitation gauge. The precipitation accuracy after correction approaches that of the pit gauge. The correction method developed is simple and feasible. 展开更多
关键词 precipitation evaluation stations intercomparison measurements precipitation measurement errors correction method
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Analogue correction method of errors and its application to numerical weather prediction 被引量:9
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作者 高丽 任宏利 +1 位作者 李建平 丑纪范 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第4期882-889,共8页
In this paper, an analogue correction method of errors (ACE) based on a complicated atmospheric model is further developed and applied to numerical weather prediction (NWP). The analysis shows that the ACE can eff... In this paper, an analogue correction method of errors (ACE) based on a complicated atmospheric model is further developed and applied to numerical weather prediction (NWP). The analysis shows that the ACE can effectively reduce model errors by combining the statistical analogue method with the dynamical model together in order that the information of plenty of historical data is utilized in the current complicated NWP model, Furthermore, in the ACE, the differences of the similarities between different historical analogues and the current initial state are considered as the weights for estimating model errors. The results of daily, decad and monthly prediction experiments on a complicated T63 atmospheric model show that the performance of the ACE by correcting model errors based on the estimation of the errors of 4 historical analogue predictions is not only better than that of the scheme of only introducing the correction of the errors of every single analogue prediction, but is also better than that of the T63 model. 展开更多
关键词 numerical weather prediction analogue correction method of errors reference state analogue-dynamical model
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Application of the Analogue-Based Correction of Errors Method in ENSO Prediction 被引量:9
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作者 REN Hong-Li LIU Ying +2 位作者 JIN Fei-Fei YAN Yu-Ping LIU Xiang-Wen 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第2期157-161,共5页
In this study, a method of analogue-based correction of errors(ACE) was introduced to improve El Ni?o-Southern Oscillation(ENSO) prediction produced by climate models. The ACE method is based on the hypothesis that th... In this study, a method of analogue-based correction of errors(ACE) was introduced to improve El Ni?o-Southern Oscillation(ENSO) prediction produced by climate models. The ACE method is based on the hypothesis that the flow-dependent model prediction errors are to some degree similar under analogous historical climate states, and so the historical errors can be used to effectively reduce such flow-dependent errors. With this method, the unknown errors in current ENSO predictions can be empirically estimated by using the known prediction errors which are diagnosed by the same model based on historical analogue states. The authors first propose the basic idea for applying the ACE method to ENSO prediction and then establish an analogue-dynamical ENSO prediction system based on an operational climate prediction model. The authors present some experimental results which clearly show the possibility of correcting the flow-dependent errors in ENSO prediction, and thus the potential of applying the ACE method to operational ENSO prediction based on climate models. 展开更多
关键词 ENSO climatic prediction error correction
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The English Teachers' Correction Strategies toward Students' Oral Errors in College
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作者 张莹 朱文宣 《海外英语》 2014年第2X期37-42,共6页
Based on the requirements of college English curriculum,college students should have natural and fluent pronunciation and intonation in their oral English.Students’ability to communicate successfully has become an ul... Based on the requirements of college English curriculum,college students should have natural and fluent pronunciation and intonation in their oral English.Students’ability to communicate successfully has become an ultimate goal for schools.Therefore,to make some requirements on English teachers’correction strategies toward students’oral errors in the procedure of teaching becomes necessary.Through researching,analyzing the listed examples and making an investigation,the author finds out that there are some problems in English teachers’attitudes and treatment toward college students’oral errors.The author hopes that her analyses and findings could help the teachers to conduct a more appropriate correction strategies which may be helpful for the teachers to manage their classrooms effectively,thus to eliminate the frustrating feelings of the students and to facilitate an efficient interaction between the teachers and the students. 展开更多
关键词 ORAL errors correction treatment
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Studies on National Preparatory Students' English Oral Errors and Corrections
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作者 李媛媛 《海外英语》 2014年第4X期55-57,共3页
This paper, based on the theory and teaching practice, presents a tentative analysis about English oral errors commonly made by university's national preparatory students. At first, I analyze the causes of oral er... This paper, based on the theory and teaching practice, presents a tentative analysis about English oral errors commonly made by university's national preparatory students. At first, I analyze the causes of oral errors, then review teachers' different attitude towards oral errors and finally propose some main principles and factors and possible strategies of oral error corrections. 展开更多
关键词 ORAL errors analysis correction strategies
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A Steady-State Errors Correction Method for Eliminating Measurement Errors
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作者 田新良 杨苹 《Journal of Donghua University(English Edition)》 EI CAS 2013年第4期298-304,共7页
This paper proposes a steady-state errors correction(SSEC)method for eliminating measurement errors.This method is based on the detections of error signal E(s)and output C(s)which generate an expected output R(s).In c... This paper proposes a steady-state errors correction(SSEC)method for eliminating measurement errors.This method is based on the detections of error signal E(s)and output C(s)which generate an expected output R(s).In comparison with the conventional solutions which are based on detecting the expected output R(s)and output C(s)to obtain error signal E(s),the measurement errors are eliminated even the error might be at a significant level.Moreover,it is possible that the individual debugging by regulating the coefficient K for every member of the multiple objectives achieves the optimization of the open loop gain.Therefore,this simple method can be applied to the weak coupling and multiple objectives system,which is usually controlled by complex controller.The principle of eliminating measurement errors is derived analytically,and the advantages comparing with the conventional solutions are depicted.Based on the SSEC method analysis,an application of this method for an active power filter(APF)is investigated and the effectiveness and viability of the scheme are demonstrated through the simulation and experimental verifications. 展开更多
关键词 measurement errors steady-state errors correction (SSEC) active power filters (APF)CLC number:TM77Document code:AArticle ID:1672-5220(2013)04-0298-07
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An Empirical Study of Using Imitation-Based Error Correction to Reduce Repeated Errors in English Writing of Rural Junior High School Students
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作者 LING Qian QIU Hong 《Sino-US English Teaching》 2011年第10期622-628,共7页
Junior high school students in rural areas constitute a particular group of English learners, for whom English writing is not only important, but also difficult. In order to find out an effective means to help them en... Junior high school students in rural areas constitute a particular group of English learners, for whom English writing is not only important, but also difficult. In order to find out an effective means to help them enhance English writing proficiency. To this end, after carefully analyzing the writing characteristics of this group of English learners, one intact class in Grade 8 of No. 14 junior middle school in Wuwei was given an experimental treatment which required them to imitate the correct examples of expressions provided by their teacher where they used to make errors. Results revealed that students in experimental class outperform their peers in control class significantly. 展开更多
关键词 selective and direct error correction imitation-based rural junior high school
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Analysis and correction of the machining errors of small plastic helical gears by ball-end milling
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作者 Gao Sande Huang Loulin and Han Baoling 《Computer Aided Drafting,Design and Manufacturing》 2012年第1期61-65,共5页
Many small-size precise plastic helical involutes gears are used in electrical appliances to transmit rotary movements con- tinuously and smoothly. Ball-end milling is an effective method for trial manufacture or smal... Many small-size precise plastic helical involutes gears are used in electrical appliances to transmit rotary movements con- tinuously and smoothly. Ball-end milling is an effective method for trial manufacture or small batch production of this type of gear, but the precision of the gear is usually low. In this research, the main sources of the errors of the gear, machining errors of the tooth profile and trace of the gear obtained were analyzed. The correction amounts for these errors are then determined by using a CNC gear tester. They are used to generate a new 3D-CAD model for gear machining with better nrecision. 展开更多
关键词 small plastic helical gear CAD/CAM ball-end milling machining error CNC gear tester error correction
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A Survey on Vocational College Students' Spoken English Errors and Teacher's Error Correction Methods
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作者 Zhangchun-hua 《科技信息》 2010年第36期134-136,共3页
During the process of language learning,it is unavoidable for learners to make some errors.As a teacher,it is very important to correct students' errors in a proper way.This paper explores the spoken English error... During the process of language learning,it is unavoidable for learners to make some errors.As a teacher,it is very important to correct students' errors in a proper way.This paper explores the spoken English errors correction in the classes of vocational college.Based on the study of one English class in a vocational college,the types and causes of spoken English errors are generalized.Then,the paper elaborates several ways employed by the teacher to correct students' errors.Finally,some implications for correcting the spoken English errors in vocational college are discussed. 展开更多
关键词 英语 语言学习 口语 学习方法
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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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Error Analysis and Error Correction in English Learning
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作者 罗赟梅 《英语广场(学术研究)》 2012年第2期86-88,共3页
As a field in applied linguistics, error analysis is not only an instrument for language acquisition research but also an auxiliary tool for language teaching. It plays a significant role both in exploring the learnin... As a field in applied linguistics, error analysis is not only an instrument for language acquisition research but also an auxiliary tool for language teaching. It plays a significant role both in exploring the learning rules and improving the teaching of foreign languages. With this information, teachers could adjust their teaching plan and make their teaching more effective. In this paper I present some common errors that my students make in their learning process. Based on these, a further elaboration on how to correct errors, including the attitudes to them, the integrative principles, the concrete methods and techniques for error correction is discussed as well. 展开更多
关键词 errors CAUSES error analysis correction
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Error Correction in the Classroom
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作者 梁亚兰 《海外英语》 2011年第9X期54-55,共2页
Making errors is inevitable in learning a second language.This paper discusses the following questions concerning errors correction in the classroom:Whether to correct errors,what time to correct errors,who corrects e... Making errors is inevitable in learning a second language.This paper discusses the following questions concerning errors correction in the classroom:Whether to correct errors,what time to correct errors,who corrects errors and how to correct errors respectively. 展开更多
关键词 error error correction MISTAKE
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Calculation and correction of magnetic object positioning error caused by magnetic field gradient tensor measurement 被引量:5
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作者 WANG Sansheng ZHANG Mingji +1 位作者 ZHANG Ning GUO Qiang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第3期456-461,共6页
Magnetic field gradient tensor measurement is an important technique to obtain position information of magnetic objects. When using magnetic field sensors to measure magnetic field gradient as the coefficients of tens... Magnetic field gradient tensor measurement is an important technique to obtain position information of magnetic objects. When using magnetic field sensors to measure magnetic field gradient as the coefficients of tensor, field differentiation is generally approximated by field difference. As a result, magnetic objects positioning by magnetic field gradient tensor measurement always involves an inherent error caused by sensor sizes, leading to a reduction in detectable distance and detectable angle. In this paper, the inherent positioning error caused by magnetic field gradient tensor measurement is calculated and corrected by iterations based on the systematic position error distribution patterns. The results show that, the detectable distance range and the angle range of an ac magnetic object(2.44 Am^2@1 kHz) can be increased from(0.45 m, 0.75 m),(0?, 25?) to(0.30 m, 0.80 m),(0?,80?), respectively. 展开更多
关键词 magnetic dipole magnetic gradient tensor positioning error error correction
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An Online Model Correction Method Based on an Inverse Problem:Part I—Model Error Estimation by Iteration 被引量:3
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作者 XUE Haile SHEN Xueshun CHOU Jifan 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第10期1329-1340,共12页
Errors inevitably exist in numerical weather prediction (NWP) due to imperfect numeric and physical parameterizations. To eliminate these errors, by considering NWP as an inverse problem, an unknown term in the pred... Errors inevitably exist in numerical weather prediction (NWP) due to imperfect numeric and physical parameterizations. To eliminate these errors, by considering NWP as an inverse problem, an unknown term in the prediction equations can be estimated inversely by using the past data, which are presumed to represent the imperfection of the NWP model (model error, denoted as ME). In this first paper of a two-part series, an iteration method for obtaining the MEs in past intervals is presented, and the results from testing its convergence in idealized experiments are reported. Moreover, two batches of iteration tests were applied in the global forecast system of the Global and Regional Assimilation and Prediction System (GRAPES-GFS) for July-August 2009 and January-February 2010. The datasets associated with the initial conditions and sea surface temperature (SST) were both based on NCEP (National Centers for Environmental Prediction) FNL (final) data. The results showed that 6th h forecast errors were reduced to 10% of their original value after a 20-step iteration. Then, off-line forecast error corrections were estimated linearly based on the 2-month mean MEs and compared with forecast errors. The estimated error corrections agreed well with the forecast errors, but the linear growth rate of the estimation was steeper than the forecast error. The advantage of this iteration method is that the MEs can provide the foundation for online correction. A larger proportion of the forecast errors can be expected to be canceled out by properly introducing the model error correction into GRAPES-GFS. 展开更多
关键词 model error past data inverse problem error estimation model correction GRAPES-GFS
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Performance analysis and design of MIMO-OFDM system using concatenated forward error correction codes 被引量:3
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作者 Arun Agarwal Saurabh N.Mehta 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第6期1322-1343,共22页
This work investigates the performance of various forward error correction codes, by which the MIMO-OFDM system is deployed. To ensure fair investigation, the performance of four modulations, namely, binary phase shif... This work investigates the performance of various forward error correction codes, by which the MIMO-OFDM system is deployed. To ensure fair investigation, the performance of four modulations, namely, binary phase shift keying(BPSK), quadrature phase shift keying(QPSK), quadrature amplitude modulation(QAM)-16 and QAM-64 with four error correction codes(convolutional code(CC), Reed-Solomon code(RSC)+CC, low density parity check(LDPC)+CC, Turbo+CC) is studied under three channel models(additive white Guassian noise(AWGN), Rayleigh, Rician) and three different antenna configurations(2×2, 2×4, 4×4). The bit error rate(BER) and the peak signal to noise ratio(PSNR) are taken as the measures of performance. The binary data and the color image data are transmitted and the graphs are plotted for various modulations with different channels and error correction codes. Analysis on the performance measures confirm that the Turbo + CC code in 4×4 configurations exhibits better performance. 展开更多
关键词 bit error rate (BER) convolutional CODE (CC) forward error correction peak signal to noise ratio (PSNR) Turbo CODE
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Author Correction:Recent Progress in Interfacial Dipole Engineering for Perovskite Solar Cells
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作者 Yinyi Ma Jue Gong +1 位作者 Peng Zeng Mingzhen Liu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期500-500,共1页
In the version of this Article originally published online,there was an error in the schematics of Figures 2b and 2c.These errors have now been corrected in the original article.
关键词 corrected error Solar
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Quantum computation and error correction based on continuous variable cluster states 被引量:4
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作者 Shuhong Hao Xiaowei Deng +3 位作者 Yang Liu Xiaolong Su Changde Xie Kunchi Peng 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第6期18-27,共10页
Measurement-based quantum computation with continuous variables,which realizes computation by performing measurement and feedforward of measurement results on a large scale Gaussian cluster state,provides a feasible w... Measurement-based quantum computation with continuous variables,which realizes computation by performing measurement and feedforward of measurement results on a large scale Gaussian cluster state,provides a feasible way to implement quantum computation.Quantum error correction is an essential procedure to protect quantum information in quantum computation and quantum communication.In this review,we briefly introduce the progress of measurement-based quantum computation and quantum error correction with continuous variables based on Gaussian cluster states.We also discuss the challenges in the fault-tolerant measurement-based quantum computation with continuous variables. 展开更多
关键词 quantum computation quantum error correction continuous variables cluster state
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Tooth surface error correction of hypoid gears machined by duplex helical method 被引量:5
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作者 WU Shun-xing YAN Hong-zhi +3 位作者 WANG Zhi-yong BI Ren-gui CHEN Zhi ZHU Peng-fei 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第5期1402-1411,共10页
In this work,synchronous cutting of concave and convex surfaces was achieved using the duplex helical method for the hypoid gear,and the problem of tooth surface error correction was studied.First,the mathematical mod... In this work,synchronous cutting of concave and convex surfaces was achieved using the duplex helical method for the hypoid gear,and the problem of tooth surface error correction was studied.First,the mathematical model of the hypoid gears machined by the duplex helical method was established.Second,the coordinates of discrete points on the tooth surface were obtained by measurement center,and the normal errors of the discrete points were calculated.Third,a tooth surface error correction model is established,and the tooth surface error was corrected using the Levenberg-Marquard algorithm with trust region strategy and least square method.Finally,grinding experiments were carried out on the machining parameters obtained by Levenberg-Marquard algorithm with trust region strategy,which had a better effect on tooth surface error correction than the least square method.After the tooth surface error is corrected,the maximum absolute error is reduced from 30.9μm before correction to 6.8μm,the root mean square of the concave error is reduced from 15.1 to 2.1μm,the root mean square of the convex error is reduced from 10.8 to 1.8μm,and the sum of squared errors of the concave and convex surfaces was reduced from 15471 to 358μm^(2).It is verified that the Levenberg-Marquard algorithm with trust region strategy has a good accuracy for the tooth surface error correction of hypoid gear machined by duplex helical method. 展开更多
关键词 duplex helical method hypoid gear error measurement Levenberg–Marquard algorithm with trust region strategy correction of tooth surface error
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