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On the Effects of Negative Transfer of Native Language to Business English Correspondence from the Analysis on the Errors Madein Clarity
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作者 张雯娟 《海外英语》 2014年第9X期154-155,共2页
This paper is an attempt to analyse the role of negative transfer in the acquisition of business English correspondence through the analysis of errors made in learners’writings.The analysis is focused on errors made ... This paper is an attempt to analyse the role of negative transfer in the acquisition of business English correspondence through the analysis of errors made in learners’writings.The analysis is focused on errors made violating clarity.Through the contrast between those errors and the normative samples,one of the deep-rooted reasons that prohibits learners to make the correspondences be clarified are discovered,which is the negative transfer resulted from different thought patterns affected by the cultural diversities. 展开更多
关键词 NEGATIVE transfer BUSINESS English CORRESPONDENCE
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高接触比螺旋锥齿面修形方法及动态特性研究
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作者 李建国 徐国胜 《机床与液压》 北大核心 2024年第1期98-104,共7页
为抑制高接触比螺旋锥齿轮传动的振动,提出一种新的高阶齿面修形方法。根据高接触比螺旋锥齿轮的啮合特点,提出一种新的修形曲线,采用辅助齿面修形方法生成高阶修形螺旋锥齿轮。在考虑齿变形的情况下,计算了高阶修正弧齿锥齿轮传动的载... 为抑制高接触比螺旋锥齿轮传动的振动,提出一种新的高阶齿面修形方法。根据高接触比螺旋锥齿轮的啮合特点,提出一种新的修形曲线,采用辅助齿面修形方法生成高阶修形螺旋锥齿轮。在考虑齿变形的情况下,计算了高阶修正弧齿锥齿轮传动的载荷传递误差和啮合冲击,在此基础上建立了降低高接触比螺旋锥齿轮传动的载荷传递误差和啮合冲击的优化模型。仿真结果表明:与二阶修形弧齿锥齿轮相比,高阶齿面修形方法不仅可以有效降低高接触比螺旋锥齿的载荷传递误差、啮合冲击和动态负载系数,而且可以提高其在全速范围内的动态性能。 展开更多
关键词 高接触比 螺旋锥齿轮 高阶齿面修形 载荷传递误差
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高阶声学相对传递函数的参数化辨识
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作者 徐赋民 张二亮 付康 《声学技术》 CSCD 北大核心 2024年第2期281-286,共6页
针对声学相对传递函数的模型阶次高以及辨识数据信噪比低的问题,文章运用频域系统辨识方法,建立了一种相对传递函数的高精度参数化辨识方法。首先建立变量带误差辨识框架,采用周期扫频信号作为声源激励,给出声学相对传递函数的极大似然... 针对声学相对传递函数的模型阶次高以及辨识数据信噪比低的问题,文章运用频域系统辨识方法,建立了一种相对传递函数的高精度参数化辨识方法。首先建立变量带误差辨识框架,采用周期扫频信号作为声源激励,给出声学相对传递函数的极大似然算法。然后使用正交福赛斯(Forsythe)多项式解决高阶系统带来的雅克比矩阵条件数过高的数值问题,并建立了极大似然方法所需初始值的生成策略。最后通过仿真算例和实验测试,验证文中方法在混响声场下辨识声学相对传递函数的有效性。 展开更多
关键词 声学相对传递函数 变量带误差 周期扫频 极大似然 福赛斯(Forsythe)多项式
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基于多面体模型的电机装配误差分析
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作者 阮天昊 张永亮 王书楠 《农业装备与车辆工程》 2024年第1期162-166,共5页
电机装配时各零件的偏差累积会影响电机气隙,导致电机性能与装配质量下降,因此需对装配后电机定转子间的气隙进行公差分析。为做好公差分析,以电机气隙作为装配功能要求,建立装配偏差传递路径上的多面体模型,对串并联装配结构的多面体... 电机装配时各零件的偏差累积会影响电机气隙,导致电机性能与装配质量下降,因此需对装配后电机定转子间的气隙进行公差分析。为做好公差分析,以电机气隙作为装配功能要求,建立装配偏差传递路径上的多面体模型,对串并联装配结构的多面体模型进行闵可夫斯基求和与求交运算,最终得到装配体气隙沿径向平动的变化范围。运用3DCS基于蒙特卡洛法对电机气隙进行仿真,验证了多面体模型法求解所得装配误差的准确性和合理性,对电机的公差设计具有一定的参考价值。 展开更多
关键词 电机 多面体模型 公差分析 串并联装配结构 误差传递
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白光显微干涉测量曲面样品形貌误差的校正方法
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作者 李赫然 袁群 +7 位作者 范筱昕 张佳乐 马剑秋 乔文佑 高志山 郭珍艳 雷李华 傅云霞 《应用光学》 CAS 北大核心 2024年第2期422-429,共8页
白光显微干涉术在平面阶跃型结构的形貌测量中具有显著优势。但在测量斜率变化的曲面样品时,由于物镜数值孔径的限制,样品表面反射光随着斜率的增大而减弱,干涉信号对比度降低,导致形貌测量结果的误差增大。基于表面传递函数(surface tr... 白光显微干涉术在平面阶跃型结构的形貌测量中具有显著优势。但在测量斜率变化的曲面样品时,由于物镜数值孔径的限制,样品表面反射光随着斜率的增大而减弱,干涉信号对比度降低,导致形貌测量结果的误差增大。基于表面传递函数(surface transfer function, STF)计算得到的逆滤波器可用于校正曲面样品的形貌测量误差,但现有方法的逆滤波器增益受限,无法有效提升频谱中的高频信号,对最大可测量斜率的提升有限。针对该问题,提取由白光干涉仪特性参数计算获得的虚拟STF的模作为振幅增益函数,由干涉图傅里叶变换得到的实测STF的相位作为相位补偿函数,形成虚实融合型逆滤波器,据此实现白光干涉仪曲面形貌测量误差的校正。应用该方法校正微球的形貌测量结果,校正后最大可测量斜率从8.09°提升到21.20°,均方根误差从0.545 5μm降低至0.175 9μm,实现了提升曲面样品的最大可测量斜率和减小测量误差的目的,有效提升了仪器针对曲面样品的测量范围。 展开更多
关键词 白光显微干涉仪 表面传递函数 表面形貌测量 误差校正 逆滤波算法
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The calculation of the Reproducibility Error in the technological system with the clamp on the gas power
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作者 沈兴东 郑士成 《自动化博览》 2011年第S2期169-172,共4页
The paper deduced a calculation formula by the classic control theory on the Reproducibility Error of parts processing in the technology system,the flexible clamp system, with the clamping device on the gas power,and ... The paper deduced a calculation formula by the classic control theory on the Reproducibility Error of parts processing in the technology system,the flexible clamp system, with the clamping device on the gas power,and analyzed its influencing factor with examples,the Reproducibility Error law:\ The larger the diameter of the cylinder,the smaller the error; the slower the tool speed,(k values smaller),the smaller the error. 展开更多
关键词 CYLINDER CLAMPING REPRODUCIBILITY error transfer function ovality
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金属连接件对保温与结构一体化墙体热工性能影响实验研究及模拟验证
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作者 李永 郝文辉 +2 位作者 赵彦彦 郭朝辉 任治立 《粉煤灰综合利用》 CAS 2024年第1期163-167,共5页
为了验证采用模拟计算的方法研究金属连接件对保温与结构一体化墙体热工性能影响的准确性与可靠性,首先依据(GB/T 13475—2008)《绝热稳态传热性质的测定标定和防护热箱法》规定的防护热箱法,制作实验墙体,并在实验台上分别对锚入金属... 为了验证采用模拟计算的方法研究金属连接件对保温与结构一体化墙体热工性能影响的准确性与可靠性,首先依据(GB/T 13475—2008)《绝热稳态传热性质的测定标定和防护热箱法》规定的防护热箱法,制作实验墙体,并在实验台上分别对锚入金属连接件数量为3、6和9个的保温与结构一体化墙体进行了实验研究,获取了墙体的实测传热系数。随后利用Airpak计算流体力学软件建立与实验研究相同的三组模型,并设置了相同的热室与冷室温度工况,分别计算其传热系数。最后对实测结果与模拟结果进行了对比。结果表明:锚入金属连接件数量为3、6和9个时的保温与结构一体化墙体平均相对误差分别为4.92%、4.69%和3.96%,模拟计算误差均在5%范围内,满足工程计算要求。 展开更多
关键词 防护热箱法 金属连接件 传热系数 相对误差
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惯导系统传递对准模型的研究进展综述
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作者 徐庚 何永旭 《无人系统技术》 2024年第1期36-49,共14页
初始对准是惯导系统开启工作后必须经历的阶段,而传递对准则是一种特殊的动基座初始对准技术,可有效提高武器装备的快速反应和精准打击能力。对惯导系统传递对准模型的研究进展进行了综合评述。首先,从姿态误差的定义出发,系统归纳了ϕ_... 初始对准是惯导系统开启工作后必须经历的阶段,而传递对准则是一种特殊的动基座初始对准技术,可有效提高武器装备的快速反应和精准打击能力。对惯导系统传递对准模型的研究进展进行了综合评述。首先,从姿态误差的定义出发,系统归纳了ϕ_(n)角误差模型、ϕ_(m) 角误差模型和相对姿态对准模型,对比分析了三类误差模型的特点。其次,给出了导航速度、相对速度和惯性速度的定义,理论推导了三种导航速度误差方程。然后,介绍了传递对准的量测模型,并重点归纳了基于相对姿态理论的文献所采用的量测模型。最后,讨论了传递对准有待解决的技术问题和未来研究方向。综述表明,误差的数学定义和参考坐标系以及匹配参数决定了传递对准模型的丰富性,在实际使用时,可以根据应用背景以及使用条件选择相应的传递对准模型,而在误差建模、误差激励、性能评估等方面,传递对准技术都有待进一步研究。 展开更多
关键词 惯导系统 传递对准 误差模型 状态估计 姿态误差 速度误差 相对姿态
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基于多源数据融合和迁移学习的超差CVT在线辨识方法研究
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作者 于航舰 冯科 《电气传动自动化》 2024年第1期56-60,共5页
针对现有电容式电压互感器(CVT)在线评估方法仅使用CVT在线测量数据,数据维度低、可靠性差、精度低的问题,本文提出了一种基于多元数据融合和迁移学习的超差CVT在线辨识方法,首先通过对CVT的电气属性特征和工况属性特征进行融合,然后采... 针对现有电容式电压互感器(CVT)在线评估方法仅使用CVT在线测量数据,数据维度低、可靠性差、精度低的问题,本文提出了一种基于多元数据融合和迁移学习的超差CVT在线辨识方法,首先通过对CVT的电气属性特征和工况属性特征进行融合,然后采用“离线训练-在线建模”的方式和迁移学习算法,构建了基于NARX神经网络的超差CVT在线辨识模型,在不停电条件下实现了对超差CVT的在线辨识。仿真数据表明,该方法能准确辨识CVT超误差状态,状态识别准确率高于99%,与现有技术对比,验证了该方法的准确性与实用性。 展开更多
关键词 电容式电压互感器 误差状态 多源数据融合 迁移学习
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基于自由度约束的元动作单元误差传递路径识别方法 被引量:1
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作者 李健 张根保 +1 位作者 冉琰 王勇勤 《中国机械工程》 EI CAS CSCD 北大核心 2023年第2期135-141,共7页
准确识别元动作单元的误差传递路径是误差分析的前提。基于机械系统中自由度约束的概念,提出了一种利用自由度约束判断误差传递路径的新方法。首先,通过分析元动作单元功能和结构,确定精度输出件自由度约束要求并初步确定误差传递路径;... 准确识别元动作单元的误差传递路径是误差分析的前提。基于机械系统中自由度约束的概念,提出了一种利用自由度约束判断误差传递路径的新方法。首先,通过分析元动作单元功能和结构,确定精度输出件自由度约束要求并初步确定误差传递路径;然后,分析路径中零件结合面的约束属性,并沿误差传递路径计算精度输出件的自由度约束属性。将得到的自由度约束属性与自由度约束要求进行对比,确定误差传递路径。与传统方法相比,所提方法极大提高了误差传递路径分析和识别的效率。 展开更多
关键词 元动作单元 装配误差 误差传递路径 自由度
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A Study of Syntactic Errors in College English Writing
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作者 吕玥玥 李晶 《海外英语》 2014年第9X期270-273,共4页
Writing is an integrated task which can test language learners’ability towards vocabulary,grammar,syntax,etc,and is therefore favored by many examinations both at home and abroad.However,Chinese students tend to perf... Writing is an integrated task which can test language learners’ability towards vocabulary,grammar,syntax,etc,and is therefore favored by many examinations both at home and abroad.However,Chinese students tend to perform poorly in English writing.The paper randomly chooses 30 compositions from sophomores from a Beijing university and picks out the syntactic errors,which can hardly be corrected merely by reference books and is therefore of great value.These errors are classified into eight types and the reasons are put forward in order for students to avoid them in future studies. 展开更多
关键词 COLLEGE ENGLISH WRITING SYNTACTIC errorS NEGATIVE
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Negative transfer in Chinese college students' English writing
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作者 DONG Juan HAN Ge-ling 《Sino-US English Teaching》 2009年第8期9-16,共8页
关键词 英语教学 英语写作 阅读 翻译 大学英语 中国
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A Discussion on Dealing With Chinese Transfer in English Teaching
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作者 JIN Zhao-hui ZHOU Qing-yan TAO yu 《Sino-US English Teaching》 2012年第10期1601-1606,共6页
关键词 英语教学 中国 转让 外语学习 交易 英语教师 英语学习 迁移理论
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A Study on Negative Transfer of Mother Tongue in English Majors' Writings
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作者 李惠 《海外英语》 2015年第18期177-179,共3页
Based on the Error Analysis theory and Contrastive Analysis theory,this thesis aims to investigate the phenomenon of negative transfer of mother tongue at the levels of substance,lexis and syntax by taking advantage o... Based on the Error Analysis theory and Contrastive Analysis theory,this thesis aims to investigate the phenomenon of negative transfer of mother tongue at the levels of substance,lexis and syntax by taking advantage of quantitative analysis method,and an attempt is made to analyze and classify writing errors in L2 writings by English majors.Anyhow,it is hoped that current research can achieve the purpose of avoiding the negative transfer of mother tongue and to improve English majors’writing capability accordingly. 展开更多
关键词 error ANALYSIS CONTRASTIVE ANALYSIS negative transfer of MOTHER TONGUE English WRITING
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Analysis of vocational students in English writing errors
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作者 Shaanxi Technical College of Finance and Economics Liu Daiqi 《科技信息》 2011年第8期148-148,共1页
Based on error analysis theory,this thesis studies Chinese EFL learners 'writings from the perspective of errors.It proceeds to summarize some features of students' errors to remind English teachers to be more... Based on error analysis theory,this thesis studies Chinese EFL learners 'writings from the perspective of errors.It proceeds to summarize some features of students' errors to remind English teachers to be more aware of them.With abundant methodological enlightenment to share,the thesis calls for more effective and workable ways to correct learners 'errors. 展开更多
关键词 中国 英语 学习方法 学生
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A Study on Negative Language Transfer in the English Instructions of Electronic Appliance
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作者 肖婷 《疯狂英语(理论版)》 2018年第4期24-26,共3页
Transfer occurs as long as second language learning goes on. In the C —E translation of instructions of goods,transfer occurs as well. It is necessary to give a through study into those negative transfers in the inst... Transfer occurs as long as second language learning goes on. In the C —E translation of instructions of goods,transfer occurs as well. It is necessary to give a through study into those negative transfers in the instructions to improve the quality of translation. This paper takes the English instructions of electronic appliance in the New Century Supermarket in N anchang University as the subjects. Through a qualitative and a quantitative study of the subjects, the author concludes that negative transfer can be found here and there in the English instructions-negative transfer at lexical level, syntactical level and discourse level, negative transfer at syntactical level having the highest frequency. This paper also explores the reason why the phenomena occurs. 展开更多
关键词 NEGATIVE transfer ENGLISH INSTRUCTIONS CONTRASTIVE ANALYSIS error ANALYSIS
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Discussion on Negative Transfer of Chinese on Senior School Students' Writing
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作者 陈权旺 《海外英语》 2013年第14期270-272,共3页
There commonly exists a phenomenon of negative transfer of Chinese in our students' English writing. Grammar, vocabulary, and expression are marked by the interference of Chinese which greatly impedes the improvem... There commonly exists a phenomenon of negative transfer of Chinese in our students' English writing. Grammar, vocabulary, and expression are marked by the interference of Chinese which greatly impedes the improvement of the students' writing communicative competence. This is mainly due to the inadequacy of the students' language input. In view of the present situation, this paper aims to analyze some typical errors that the senior school students (Grade l)make in their writing so as to reveal the tact that during the process of second language acquisition, learners tend to transfer some of their Ll features into the target language in the field of phonetic, vocabulary, especially in the field of grammar. Therefore. the study of the Ll transfer and the error analysis are crucial in the research of the writing of a L2 and it plays an important role in the teaching and learning of a L2. 展开更多
关键词 NEGATIVE transfer errorS analysis INPUT of recitat
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A Brief Analysis of Negative Transfer of Chinese on the English Writings
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作者 彭偲 《海外英语》 2012年第15期109-113,133,共6页
Based on the researches of language transfer,contrastive analysis and error analysis,this paper tries to investigate the negative transfer of Chinese on Chinese students'English writings from the perspective of sy... Based on the researches of language transfer,contrastive analysis and error analysis,this paper tries to investigate the negative transfer of Chinese on Chinese students'English writings from the perspective of syntax.During one and a half months'teaching practice in Shannxi Hanzhong No.1 Middle School,the author lived through the real teaching process and found that there were lots of problems in students'English writings.The author makes a contrastive study of the different characteristics existing in Chinese and English languag es at the level of syntax,and analyses the typical syntactic errors appearing in the 60 students'English compositions collected from one or dinary class.These syntactic errors are caused by the negative transfer of Chinese.The purpose of the investigation is to study in what pat tern students have been influenced by Chinese in their English writings.Based on the findings and analysis of the mother tongue transfer on English writings,some implications are also provided in order to help minimize or eliminate the interference of negative transfer of the Chinese in students'English writings and improve the teaching and learning of English. 展开更多
关键词 NEGATIVE transfer MOTHER TONGUE English writings s
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A Case Study for the Influence of Mother Tongue Transfer in Non-English Majors'Spoken English
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作者 唐春艳 《海外英语》 2018年第11期244-246,共3页
In field of Second Language Acquisition, mother tongue has both positive transfer and negative transfer. Using proper foreign language learning strategies can effectively avoid the negative transfer of mother tongue a... In field of Second Language Acquisition, mother tongue has both positive transfer and negative transfer. Using proper foreign language learning strategies can effectively avoid the negative transfer of mother tongue and improve learners' oral English competence. Based on the theories of language transfer, this thesis mainly focuses on, error analysis and inter-language theory. In recent years, more and more scholars have studied the transfer of mother tongue in the field of College English teaching, and the points are also different. However, there is little research on the influence of mother tongue transfer in non English majors' spoken English. This case study chooses a non-English major student as the research object, and analyzes the causes of errors and linguistic categories in spoken English. The motivation of this student for learning spoken English is to attend graduate oral interview and TOEFL. This subject were asked to attend two oral tests and an interview. Through the anglicizing and investigating of the experimental data, the author finds that the errors in spoken English by the student are mainly affected by the negative transfer and negative cultural transfer of mother tongue. The errors of spoken language transfer are mainly reflected in phonetics, vocabulary, syntax and pragmatics. This thesis will focus on three aspects: vocabulary, syntax and pragmatics. The research results also show that the most difficult problem for non English majors in the course of spoken English is the lack of vocabulary. And so it is difficult to express their ideas in English. 展开更多
关键词 mother tongue transfer errorS spoken English teaching spoken English leaning
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An Analysis of Errors Made by English Speakers in Pronouncing Neutral Tone in Mandarin
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作者 唐中黎 《海外英语》 2010年第10X期236-238,共3页
对于母语为英语的外国人来说,汉语四个声调是学习中的难点。而作为汉语声调一大特点的轻声更需要予以重视。由于英语母语的负迁移,许多人将英语语调与汉语声调混淆,以致发音错误。该文基于对轻声做出发声实验和听辨实验的结论,分析了母... 对于母语为英语的外国人来说,汉语四个声调是学习中的难点。而作为汉语声调一大特点的轻声更需要予以重视。由于英语母语的负迁移,许多人将英语语调与汉语声调混淆,以致发音错误。该文基于对轻声做出发声实验和听辨实验的结论,分析了母语为英语的外国人轻声输出时的发生错误表现,并试图阐明原因。 展开更多
关键词 neutral-tone non-tone language negative transfer PRONUNCIATION errorS
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