Based on the theory of elastic mechanics and material mechanics, the orientation precision of the hohl schaft kegel（HSK） tooling system in static and dynamic states is theoretically and experimentally studied. The r...Based on the theory of elastic mechanics and material mechanics, the orientation precision of the hohl schaft kegel（HSK） tooling system in static and dynamic states is theoretically and experimentally studied. The relation between the clamping force and the shank taper is obtained. And a proper clamping force is found to be essential to assure the axial and radial orientation precisions of the HSK tooling system in high speed machining （HSM）. Analytical results show that the reason why the HSK tooling system can keep high precision at the high rotational speed is that the actual axial clamping force keeps the two surfaces of the shank and the spindle in contact all the time.展开更多
According to the structure of the hohl schaft kegel（HSK） tooling system and its working principle, a mechanical model of the HSK tooling system is established. Major factors influencing the stiffness of the system a...According to the structure of the hohl schaft kegel（HSK） tooling system and its working principle, a mechanical model of the HSK tooling system is established. Major factors influencing the stiffness of the system are analyzed and the relationship between the load and the manufacturing quality is obtained. The basic rule of the stiffness variation is presented and the theoretical analysis is in a good agreement with experimental results. The dynamic stiffness must also be considered to evaluate the performance of the tooling system besides the staticstiffness. Finally, the selecting principles of the HSK types are proposed and their optimum operating conditions are established.展开更多
“是”字句是对外汉语教学中的一种重要句型,汉语作为第二语言的学习者在日常的口语交际和书面表达中使用频率较高。然而,由于汉语和英语语言在语法结构、语义表达等方面的差异,使得留学生在学习“是”字句时常常出现偏误。论文以对比...“是”字句是对外汉语教学中的一种重要句型,汉语作为第二语言的学习者在日常的口语交际和书面表达中使用频率较高。然而,由于汉语和英语语言在语法结构、语义表达等方面的差异,使得留学生在学习“是”字句时常常出现偏误。论文以对比语言学理论为指导,以HSK动态作文语料库为基础,结合对比研究和语料研究的方法,分析归纳英国、加拿大、美国等7个母语为英语背景的留学生在学习“是”字句时的偏误类型和原因,并提出针对性的教学策略和建议,以期为汉语作为第二语言的教与学提供理论和实践指导,丰富和深化相关研究。The “是” sentence is an important sentence pattern in the teaching of Chinese as a foreign language, and learners of Chinese as a second language use it more frequently in their daily oral communication and written expression. However, due to the differences between Chinese and English in terms of grammatical structure and semantic expression, international students often make mistakes when learning “是”-sentences. Based on the theory of comparative linguistics and the HSK Dynamic Composition Corpus, the thesis analyzes and summarizes the types and causes of the errors in learning “是”-sentences of seven international students from the UK, Canada and the US with native English backgrounds by combining comparative and corpus research methods, and puts forward targeted teaching strategies and suggestions with a view to The study provides theoretical and practical guidance for the teaching and learning of Chinese as a second language, and enriches and deepens related research.展开更多
介词在虚词中是属于功能较为复杂,所涉及的范围也比较广泛的那一部分,在汉语的语法中占有很重要的地位,也因此在对外汉语教学中介词的教学成为重难点之一。本文以HSK动态作文语料库作为语料来源,主要研究日本留学生在使用介词“从”的...介词在虚词中是属于功能较为复杂,所涉及的范围也比较广泛的那一部分,在汉语的语法中占有很重要的地位,也因此在对外汉语教学中介词的教学成为重难点之一。本文以HSK动态作文语料库作为语料来源,主要研究日本留学生在使用介词“从”的时候产生偏误的类型和原因。偏误类型概括为“缺失”“多加”和“混用”,进而从介词本身、学习者个人、教学与教材方面分析偏误原因,并提出相应的教学策略,希望可以为日本留学生更好掌握和使用介词“从”提供一定帮助。Prepositions are part of virtual words that are more complex in function and involve a relatively wide range. They play a very important role in Chinese grammar. Therefore, the teaching of intermediary words in Chinese as a foreign language has become one of the key and difficult points. This article takes the HSK dynamic composition corpus as the source of the corpus, and mainly studies the types and causes of biases caused by Japanese students when using the preposition “Cong”. The type of bias is summarised as “missing”, “multiple” and “mixed”, and then analyse the causes of the bias Cong the preposition itself, the individual learner, teaching and textbook, and put forward the corresponding teaching strategy, hoping to provide some help for Japanese students to better master and use the preposition “Cong”.展开更多
文摘Based on the theory of elastic mechanics and material mechanics, the orientation precision of the hohl schaft kegel（HSK） tooling system in static and dynamic states is theoretically and experimentally studied. The relation between the clamping force and the shank taper is obtained. And a proper clamping force is found to be essential to assure the axial and radial orientation precisions of the HSK tooling system in high speed machining （HSM）. Analytical results show that the reason why the HSK tooling system can keep high precision at the high rotational speed is that the actual axial clamping force keeps the two surfaces of the shank and the spindle in contact all the time.
文摘According to the structure of the hohl schaft kegel（HSK） tooling system and its working principle, a mechanical model of the HSK tooling system is established. Major factors influencing the stiffness of the system are analyzed and the relationship between the load and the manufacturing quality is obtained. The basic rule of the stiffness variation is presented and the theoretical analysis is in a good agreement with experimental results. The dynamic stiffness must also be considered to evaluate the performance of the tooling system besides the staticstiffness. Finally, the selecting principles of the HSK types are proposed and their optimum operating conditions are established.
文摘“是”字句是对外汉语教学中的一种重要句型,汉语作为第二语言的学习者在日常的口语交际和书面表达中使用频率较高。然而,由于汉语和英语语言在语法结构、语义表达等方面的差异,使得留学生在学习“是”字句时常常出现偏误。论文以对比语言学理论为指导,以HSK动态作文语料库为基础,结合对比研究和语料研究的方法,分析归纳英国、加拿大、美国等7个母语为英语背景的留学生在学习“是”字句时的偏误类型和原因,并提出针对性的教学策略和建议,以期为汉语作为第二语言的教与学提供理论和实践指导,丰富和深化相关研究。The “是” sentence is an important sentence pattern in the teaching of Chinese as a foreign language, and learners of Chinese as a second language use it more frequently in their daily oral communication and written expression. However, due to the differences between Chinese and English in terms of grammatical structure and semantic expression, international students often make mistakes when learning “是”-sentences. Based on the theory of comparative linguistics and the HSK Dynamic Composition Corpus, the thesis analyzes and summarizes the types and causes of the errors in learning “是”-sentences of seven international students from the UK, Canada and the US with native English backgrounds by combining comparative and corpus research methods, and puts forward targeted teaching strategies and suggestions with a view to The study provides theoretical and practical guidance for the teaching and learning of Chinese as a second language, and enriches and deepens related research.
文摘介词在虚词中是属于功能较为复杂,所涉及的范围也比较广泛的那一部分,在汉语的语法中占有很重要的地位,也因此在对外汉语教学中介词的教学成为重难点之一。本文以HSK动态作文语料库作为语料来源,主要研究日本留学生在使用介词“从”的时候产生偏误的类型和原因。偏误类型概括为“缺失”“多加”和“混用”,进而从介词本身、学习者个人、教学与教材方面分析偏误原因,并提出相应的教学策略,希望可以为日本留学生更好掌握和使用介词“从”提供一定帮助。Prepositions are part of virtual words that are more complex in function and involve a relatively wide range. They play a very important role in Chinese grammar. Therefore, the teaching of intermediary words in Chinese as a foreign language has become one of the key and difficult points. This article takes the HSK dynamic composition corpus as the source of the corpus, and mainly studies the types and causes of biases caused by Japanese students when using the preposition “Cong”. The type of bias is summarised as “missing”, “multiple” and “mixed”, and then analyse the causes of the bias Cong the preposition itself, the individual learner, teaching and textbook, and put forward the corresponding teaching strategy, hoping to provide some help for Japanese students to better master and use the preposition “Cong”.
