Based on error analysis, the influence of error sources on strapdown inertial navigation systems is discussed. And the maximum permissible component tolerances are established. In order to achieve the desired accuracy...Based on error analysis, the influence of error sources on strapdown inertial navigation systems is discussed. And the maximum permissible component tolerances are established. In order to achieve the desired accuracy (defined by circular error probability), the types of appropriate sensors are chosen. The inertial measurement unit (IMU) is composed of those sensors. It is necessary to calibrate the sensors to obtain their error model coefficients of IMU. After calibration tests, the accuracy is calculated by uniform design method and it is proved that the accuracy of IMU is satisfied for the desired goal.展开更多
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
A Chebyshev fitting way for a propeller atlas across four quadrants is discussed. As an example, Chebyshev polynomial fitting results and its error analysis are given. Because it’s difficult generally to get a propel...A Chebyshev fitting way for a propeller atlas across four quadrants is discussed. As an example, Chebyshev polynomial fitting results and its error analysis are given. Because it’s difficult generally to get a propeller atlas across four quadrants, a way is used to construct an alternative with higher accuracy based on the properties. As an application example, an alternative for the propeller property of a Deep Submergence Vehicle across four quadrants is given practically and a simulation model of the four quadrants propeller for dynamic condition is set up. The model lays a foundation for DSV full operating-condition movement simulation. A lot of simulation work shows that the results are very close to the practical data and, therefore, are effective.展开更多
A three degree-of-freedom (DOF) planar changeable parallel mechanism is designed by means of control of different drive parameters. This mechanism possesses the characteristics of two kinds of parallel mechanism. Base...A three degree-of-freedom (DOF) planar changeable parallel mechanism is designed by means of control of different drive parameters. This mechanism possesses the characteristics of two kinds of parallel mechanism. Based on its topologic structure, a coordinate system for position analysis is set-up and the forward kinematic solutions are analyzed. It was found that the parallel mechanism is partially decoupled. The relationship between original errors and position-stance error of moving platform is built according to the complete differential-coefficient theory. Then we present a special example with theory values and errors to evaluate the error model, and numerical error solutions are gained. The investigations concentrating on mechanism errors and actuator errors show that the mechanism errors have more influences on the position-stance of the moving platform. It is demonstrated that improving manufacturing and assembly techniques can greatly reduce the moving platform error. The small change in position-stance error in different kinematic positions proves that the error-compensation of software can improve considerably the precision of parallel mechanism.展开更多
Based on the theories of error and error analysis, the article is trying to explore the effect of error and error analysis on SLA. Thus give some advice to the language teachers and language learners.
Though abundant work has been done in both meta-cognitive strategy and error analysis, very little has been done in the exact execution model of applying meta-cognitive strategy with the perspective of error analysis....Though abundant work has been done in both meta-cognitive strategy and error analysis, very little has been done in the exact execution model of applying meta-cognitive strategy with the perspective of error analysis. This study, presuming the construction of an integrative execution model of meta-cognitive strategy with the perspective view of error analysis, focuses on the results and discussion.展开更多
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
One of the toughest challenges facing EFL/ESL instructors is that learners find it difficult to translate what they learn in grammar class into their own writing.Moreover,they make the same mistakes repeatedly after b...One of the toughest challenges facing EFL/ESL instructors is that learners find it difficult to translate what they learn in grammar class into their own writing.Moreover,they make the same mistakes repeatedly after being corrected.In order to improve students’writing,grammatical awareness is essential.Therefore,teachers should raise the students’level of awareness of syntactic patterns and transformations of the language(Koffi,2010).In this way,teachers are not merely giving the students answers directly,but are actually showing them how to solve these syntactic puzzles by themselves.The purpose of this paper is to analyze frequently made pronoun mistakes in College ESL students’writings to offer insights into how to use pronouns accurately and to enhance learners’writing skills.This paper will look closely at a set of writings done mostly by Somali ESL students in the hope of developing some pedagogical suggestions for teaching pronouns.Frequently made pronoun mistakes will be discussed with examples from students’writing samples.展开更多
In English study,pronunciation not only influences daily communication,but also influences listening,reading and writ⁃ing ability.However,modern English education overly focuses on the uses of vocabularies and grammar...In English study,pronunciation not only influences daily communication,but also influences listening,reading and writ⁃ing ability.However,modern English education overly focuses on the uses of vocabularies and grammars,and it is short of the prac⁃tice of pronunciation.Therefore,English pronunciation errors become a common problem among non-English majors.The focus of this research is on analyzing the errors of English pronunciation through sampling thirty non-English majors in college.Based on error analysis theory,and with the assistance of pronunciation test,this study figured out several types of non-English majors’pro⁃nunciation errors in pronunciation,stress,tone and intonation these dimensions.展开更多
In this paper,we develop a multi-scalar auxiliary variables(MSAV)scheme for the Cahn-Hilliard Magnetohydrodynamics system by introducing two scalar auxiliary variables(SAV).This scheme is linear,fully decoupled and un...In this paper,we develop a multi-scalar auxiliary variables(MSAV)scheme for the Cahn-Hilliard Magnetohydrodynamics system by introducing two scalar auxiliary variables(SAV).This scheme is linear,fully decoupled and unconditionally stable in energy.Subsequently,we provide a detailed implementation procedure for full decoupling.Thus,at each time step,only a series of linear differential equations with constant coefficients need to be solved.To validate the effectiveness of our approach,we conduct an error analysis for this first-order scheme.Finally,some numerical experiments are provided to verify the energy dissipation of the system and the convergence of the proposed approach.展开更多
The error equation of a rotating inertial navigation system was introduced. The effect of the system's main error source (constant drift of gyro and zero bias of accelerometer) under rotating conditions for the sy...The error equation of a rotating inertial navigation system was introduced. The effect of the system's main error source (constant drift of gyro and zero bias of accelerometer) under rotating conditions for the system was analyzed. Validity of theoretical analysis was shown via simulation, and that provides a theoretical foundation for a rotating strap-down inertial navigation system during actual experimentation and application.展开更多
This research collects 3896 errors made by 965 Chinese students in 5 junior middle schools in Xining and then a detailed analysis is made to discover the possible causes behind these errors.This research comes to the ...This research collects 3896 errors made by 965 Chinese students in 5 junior middle schools in Xining and then a detailed analysis is made to discover the possible causes behind these errors.This research comes to the following conclusions:first,during the course of English learning in junior middle school,the students make errors mainly in six specific areas:spelling,tenses,pronouns,verb“be”,articles,and numbers;second,the learners at an elementary level produce more interlingual errors than the learners at an advanced level.Third,error fossilization is serious.展开更多
Lexical errors made by language learners frequently in the language learning process play a significant role in language teaching and learning. This paper, based on the theory of error analysis, mainly analyzes lexica...Lexical errors made by language learners frequently in the language learning process play a significant role in language teaching and learning. This paper, based on the theory of error analysis, mainly analyzes lexical errors made by Chinese senior one students in their writing and aims to find out the main types of lexical errors and the most frequent lexical errors in their writing. The results are of great significance and importance for language teaching and learning.展开更多
Aim To derive the error formulae for the algorithm of frequency response computation. Methods This algorithm was introduced theoretically, the error sources of the algorithm were analyzed and the formulae of the mai...Aim To derive the error formulae for the algorithm of frequency response computation. Methods This algorithm was introduced theoretically, the error sources of the algorithm were analyzed and the formulae of the main error were derived. Results The repeatability and stability of the processing results of the algorithm are better than those measured by 1250 Frequency Analysor. Conclusion The error formulae derived are theoretically right and practically valid.展开更多
Compensating for photovoltaic(PV)power forecast errors is an important function of energy storage systems.As PV power outputs have strong random fluctuations and uncertainty,it is difficult to satisfy the grid-connect...Compensating for photovoltaic(PV)power forecast errors is an important function of energy storage systems.As PV power outputs have strong random fluctuations and uncertainty,it is difficult to satisfy the grid-connection requirements using fixed energy storage capacity configuration methods.In this paper,a method of configuring energy storage capacity is proposed based on the uncertainty of PV power generation.A k-means clustering algorithm is used to classify weather types based on differences in solar irradiance.The power forecast errors in different weather types are analyzed,and an energy storage system is used to compensate for the errors.The kernel density estimation is used to fit the distributions of the daily maximum power and maximum capacity requirements of the energy storage system;the power and capacity of the energy storage unit are calculated at different confidence levels.The optimized energy storage configuration of a PV plant is presented according to the calculated degrees of power and capacity satisfaction.The proposed method was validated using actual operating data from a PV power station.The results indicated that the required energy storage can be significantly reduced while compensating for power forecast errors.展开更多
The analytical mathematical solutions of gas concentration and fractional gas loss for the diffusion of gas in a cylindrical coal sample were given with detailed mathematical derivations by assuming that the diffusion...The analytical mathematical solutions of gas concentration and fractional gas loss for the diffusion of gas in a cylindrical coal sample were given with detailed mathematical derivations by assuming that the diffusion of gas through the coal matrix is concentration gradient-driven and obeys the Fick’s Second Law of Diffusion.The analytical solutions were approximated in case of small values of time and the error analyses associated with the approximation were also undertaken.The results indicate that the square root relationship of gas release in the early stage of desorption,which is widely used to provide a simple and fast estimation of the lost gas,is the first term of the approximation,and care must be taken in using the square root relationship as a significant error might be introduced with increase in the lost time and decrease in effective diameter of a cylindrical coal sample.展开更多
In this paper, we study an efficient asymptotically correction of a-posteriori er- ror estimator for the numerical approximation of Volterra integro-differential equations by piecewise polynomial collocation method. T...In this paper, we study an efficient asymptotically correction of a-posteriori er- ror estimator for the numerical approximation of Volterra integro-differential equations by piecewise polynomial collocation method. The deviation of the error for Volterra integro- differential equations by using the defect correction principle is defined. Also, it is shown that for m degree piecewise polynomial collocation method, our method provides O（hm＋l） as the order of the deviation of the error. The theoretical behavior is tested on examples and it is shown that the numerical results confirm the theoretical part.展开更多
Human error,an important factor,may lead to serious results in various operational fields.The human factor plays a critical role in the risks and hazards of the maritime industry.A ship can achieve safe navigation whe...Human error,an important factor,may lead to serious results in various operational fields.The human factor plays a critical role in the risks and hazards of the maritime industry.A ship can achieve safe navigation when all operations in the engine room are conducted vigilantly.This paper presents a systematic evaluation of 20 failures in auxiliary systems of marine diesel engines that may be caused by human error.The Cognitive Reliability Error Analysis Method(CREAM)is used to determine the potentiality of human errors in the failures implied thanks to the answers of experts.Using this method,the probabilities of human error on failures were evaluated and the critical ones were emphasized.The measures to be taken for these results will make significant contributions not only to the seafarers but also to the ship owners.展开更多
Focused underwater plasma sound sources are being applied in more and more fields. Focusing performance is one of the most important factors determining transmission distance and peak values of the pulsed sound waves....Focused underwater plasma sound sources are being applied in more and more fields. Focusing performance is one of the most important factors determining transmission distance and peak values of the pulsed sound waves. The sound source’s components and focusing mechanism were all analyzed. A model was built in 3D Max and wave strength was measured on the simulation platform. Error analysis was fully integrated into the model so that effects on sound focusing performance of processing-errors and installation-errors could be studied. Based on what was practical, ways to limit the errors were proposed. The results of the error analysis should guide the design, machining, placement, debugging and application of underwater plasma sound sources.展开更多
This paper presents some results of theoretical analysis of the effects of systemerrors on bowl track performance with the assumptioris of all controlcomponents and modules having been calibrated to their nomuial perf...This paper presents some results of theoretical analysis of the effects of systemerrors on bowl track performance with the assumptioris of all controlcomponents and modules having been calibrated to their nomuial perfomcelevels such that only random errors exist of which we have little control.Theporformance levels needed to be raised considerably by anpraving in our presenttechnique of predicting bowl track resistance.展开更多
文摘Based on error analysis, the influence of error sources on strapdown inertial navigation systems is discussed. And the maximum permissible component tolerances are established. In order to achieve the desired accuracy (defined by circular error probability), the types of appropriate sensors are chosen. The inertial measurement unit (IMU) is composed of those sensors. It is necessary to calibrate the sensors to obtain their error model coefficients of IMU. After calibration tests, the accuracy is calculated by uniform design method and it is proved that the accuracy of IMU is satisfied for the desired goal.
文摘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.
文摘A Chebyshev fitting way for a propeller atlas across four quadrants is discussed. As an example, Chebyshev polynomial fitting results and its error analysis are given. Because it’s difficult generally to get a propeller atlas across four quadrants, a way is used to construct an alternative with higher accuracy based on the properties. As an application example, an alternative for the propeller property of a Deep Submergence Vehicle across four quadrants is given practically and a simulation model of the four quadrants propeller for dynamic condition is set up. The model lays a foundation for DSV full operating-condition movement simulation. A lot of simulation work shows that the results are very close to the practical data and, therefore, are effective.
基金Preject 50225519 supported by the National Outstanding Youth Science Foundation of China
文摘A three degree-of-freedom (DOF) planar changeable parallel mechanism is designed by means of control of different drive parameters. This mechanism possesses the characteristics of two kinds of parallel mechanism. Based on its topologic structure, a coordinate system for position analysis is set-up and the forward kinematic solutions are analyzed. It was found that the parallel mechanism is partially decoupled. The relationship between original errors and position-stance error of moving platform is built according to the complete differential-coefficient theory. Then we present a special example with theory values and errors to evaluate the error model, and numerical error solutions are gained. The investigations concentrating on mechanism errors and actuator errors show that the mechanism errors have more influences on the position-stance of the moving platform. It is demonstrated that improving manufacturing and assembly techniques can greatly reduce the moving platform error. The small change in position-stance error in different kinematic positions proves that the error-compensation of software can improve considerably the precision of parallel mechanism.
文摘Based on the theories of error and error analysis, the article is trying to explore the effect of error and error analysis on SLA. Thus give some advice to the language teachers and language learners.
文摘Though abundant work has been done in both meta-cognitive strategy and error analysis, very little has been done in the exact execution model of applying meta-cognitive strategy with the perspective of error analysis. This study, presuming the construction of an integrative execution model of meta-cognitive strategy with the perspective view of error analysis, focuses on the results and discussion.
文摘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.
文摘One of the toughest challenges facing EFL/ESL instructors is that learners find it difficult to translate what they learn in grammar class into their own writing.Moreover,they make the same mistakes repeatedly after being corrected.In order to improve students’writing,grammatical awareness is essential.Therefore,teachers should raise the students’level of awareness of syntactic patterns and transformations of the language(Koffi,2010).In this way,teachers are not merely giving the students answers directly,but are actually showing them how to solve these syntactic puzzles by themselves.The purpose of this paper is to analyze frequently made pronoun mistakes in College ESL students’writings to offer insights into how to use pronouns accurately and to enhance learners’writing skills.This paper will look closely at a set of writings done mostly by Somali ESL students in the hope of developing some pedagogical suggestions for teaching pronouns.Frequently made pronoun mistakes will be discussed with examples from students’writing samples.
文摘In English study,pronunciation not only influences daily communication,but also influences listening,reading and writ⁃ing ability.However,modern English education overly focuses on the uses of vocabularies and grammars,and it is short of the prac⁃tice of pronunciation.Therefore,English pronunciation errors become a common problem among non-English majors.The focus of this research is on analyzing the errors of English pronunciation through sampling thirty non-English majors in college.Based on error analysis theory,and with the assistance of pronunciation test,this study figured out several types of non-English majors’pro⁃nunciation errors in pronunciation,stress,tone and intonation these dimensions.
基金Research Project Supported by Shanxi Scholarship Council of China(2021-029)International Cooperation Base and Platform Project of Shanxi Province(202104041101019)Basic Research Plan of Shanxi Province(202203021211129)。
文摘In this paper,we develop a multi-scalar auxiliary variables(MSAV)scheme for the Cahn-Hilliard Magnetohydrodynamics system by introducing two scalar auxiliary variables(SAV).This scheme is linear,fully decoupled and unconditionally stable in energy.Subsequently,we provide a detailed implementation procedure for full decoupling.Thus,at each time step,only a series of linear differential equations with constant coefficients need to be solved.To validate the effectiveness of our approach,we conduct an error analysis for this first-order scheme.Finally,some numerical experiments are provided to verify the energy dissipation of the system and the convergence of the proposed approach.
基金the Nature Science Foundation of China under Grant No.60604019 and No.6075001
文摘The error equation of a rotating inertial navigation system was introduced. The effect of the system's main error source (constant drift of gyro and zero bias of accelerometer) under rotating conditions for the system was analyzed. Validity of theoretical analysis was shown via simulation, and that provides a theoretical foundation for a rotating strap-down inertial navigation system during actual experimentation and application.
文摘This research collects 3896 errors made by 965 Chinese students in 5 junior middle schools in Xining and then a detailed analysis is made to discover the possible causes behind these errors.This research comes to the following conclusions:first,during the course of English learning in junior middle school,the students make errors mainly in six specific areas:spelling,tenses,pronouns,verb“be”,articles,and numbers;second,the learners at an elementary level produce more interlingual errors than the learners at an advanced level.Third,error fossilization is serious.
文摘Lexical errors made by language learners frequently in the language learning process play a significant role in language teaching and learning. This paper, based on the theory of error analysis, mainly analyzes lexical errors made by Chinese senior one students in their writing and aims to find out the main types of lexical errors and the most frequent lexical errors in their writing. The results are of great significance and importance for language teaching and learning.
文摘Aim To derive the error formulae for the algorithm of frequency response computation. Methods This algorithm was introduced theoretically, the error sources of the algorithm were analyzed and the formulae of the main error were derived. Results The repeatability and stability of the processing results of the algorithm are better than those measured by 1250 Frequency Analysor. Conclusion The error formulae derived are theoretically right and practically valid.
基金supported by Nation Key R&D Program of China(2021YFE0102400).
文摘Compensating for photovoltaic(PV)power forecast errors is an important function of energy storage systems.As PV power outputs have strong random fluctuations and uncertainty,it is difficult to satisfy the grid-connection requirements using fixed energy storage capacity configuration methods.In this paper,a method of configuring energy storage capacity is proposed based on the uncertainty of PV power generation.A k-means clustering algorithm is used to classify weather types based on differences in solar irradiance.The power forecast errors in different weather types are analyzed,and an energy storage system is used to compensate for the errors.The kernel density estimation is used to fit the distributions of the daily maximum power and maximum capacity requirements of the energy storage system;the power and capacity of the energy storage unit are calculated at different confidence levels.The optimized energy storage configuration of a PV plant is presented according to the calculated degrees of power and capacity satisfaction.The proposed method was validated using actual operating data from a PV power station.The results indicated that the required energy storage can be significantly reduced while compensating for power forecast errors.
基金provided by the Science and Technology Grant of Huainan City of China (No.2013A4001)the Key Research Grant of Shanxi Province of China (No.201303027-1)
文摘The analytical mathematical solutions of gas concentration and fractional gas loss for the diffusion of gas in a cylindrical coal sample were given with detailed mathematical derivations by assuming that the diffusion of gas through the coal matrix is concentration gradient-driven and obeys the Fick’s Second Law of Diffusion.The analytical solutions were approximated in case of small values of time and the error analyses associated with the approximation were also undertaken.The results indicate that the square root relationship of gas release in the early stage of desorption,which is widely used to provide a simple and fast estimation of the lost gas,is the first term of the approximation,and care must be taken in using the square root relationship as a significant error might be introduced with increase in the lost time and decrease in effective diameter of a cylindrical coal sample.
文摘In this paper, we study an efficient asymptotically correction of a-posteriori er- ror estimator for the numerical approximation of Volterra integro-differential equations by piecewise polynomial collocation method. The deviation of the error for Volterra integro- differential equations by using the defect correction principle is defined. Also, it is shown that for m degree piecewise polynomial collocation method, our method provides O（hm＋l） as the order of the deviation of the error. The theoretical behavior is tested on examples and it is shown that the numerical results confirm the theoretical part.
文摘Human error,an important factor,may lead to serious results in various operational fields.The human factor plays a critical role in the risks and hazards of the maritime industry.A ship can achieve safe navigation when all operations in the engine room are conducted vigilantly.This paper presents a systematic evaluation of 20 failures in auxiliary systems of marine diesel engines that may be caused by human error.The Cognitive Reliability Error Analysis Method(CREAM)is used to determine the potentiality of human errors in the failures implied thanks to the answers of experts.Using this method,the probabilities of human error on failures were evaluated and the critical ones were emphasized.The measures to be taken for these results will make significant contributions not only to the seafarers but also to the ship owners.
基金Supported by the National Natural Science Foundation under Grant No.60572098
文摘Focused underwater plasma sound sources are being applied in more and more fields. Focusing performance is one of the most important factors determining transmission distance and peak values of the pulsed sound waves. The sound source’s components and focusing mechanism were all analyzed. A model was built in 3D Max and wave strength was measured on the simulation platform. Error analysis was fully integrated into the model so that effects on sound focusing performance of processing-errors and installation-errors could be studied. Based on what was practical, ways to limit the errors were proposed. The results of the error analysis should guide the design, machining, placement, debugging and application of underwater plasma sound sources.
文摘This paper presents some results of theoretical analysis of the effects of systemerrors on bowl track performance with the assumptioris of all controlcomponents and modules having been calibrated to their nomuial perfomcelevels such that only random errors exist of which we have little control.Theporformance levels needed to be raised considerably by anpraving in our presenttechnique of predicting bowl track resistance.
