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Five-axis machine is one of the most versatile machine tools in complex surface machining while the machining interference occurs easily. To avoid the adverse consequences caused by interference, interference detection, and feasible region, solution are proposed. However, with the required processing accuracy of the complex surface parts increasing, the common feasible region solution is generally difficult to achieve. The error caused by the tool orientation variation along the tool path, just the non-linear error, may exceed the specified tolerance. Considering that both the interference problem and the non-linear problem could be solved by modifying the tool orientation, this study proposes a feasible region solution for tool orientation with the constraint of non-linear error, which can avoid tool interference and achieve high geometric accuracy for tool path planning in the extreme high-precision machining. The detection region that corresponds to the tool orientation at cutter contact (CC) point is calculated to avoid the collision firstly, and the feasible region of tool orientation for a certain CC point is established. After building the tool path equations between two adjacent CC points, the relationship between the movement angles of rotation axis and the machining error is built. By considering the non-linear error of the different rotatory axes respectively, the calculation formula for the movement angle variation of the rotation axis is deduced. Finally, according to the single point non-interference feasible region of the tool angle, the non-interference feasible region for the extreme high-precision processing is constructed with the constraint of non-linear error. A comparative experiment is carried out to verify the proposed feasible region construction method. The experimental results show that with the proposed method, the profile arithmetic average error and the maximum of profile deviation are 53 μm and 71 μm, respectively, which decrease by 30.13% and 32.31% compared with the conventional non-interference feasible region. The achievements have good applicability and are significant for the improvement of processing quality, which provide guidance for the extreme high-precision machining of complex surface parts. [ABSTRACT FROM AUTHOR]

• Effects of L1 reading comprehension on L1 and L2 integrated writing were examined. • Positive reading-writing relationships were observed in L1 and L2 integrated writing. • Cross-linguistic transfer of integrated writing competence from L1 to L2 existed. Integrated writing entails synthesis of information and coordination of language skills. It constitutes an integral part of Hong Kong's language curriculum at the secondary school level. This study explored the relationships between reading comprehension, including single-text and multiple-text comprehension, and integrated writing performance in Chinese (the students' first language, L1) and English (their second language, L2). 322 students from four secondary schools participated in this study. The results of latent variable path analysis revealed that L1 single-text comprehension directly affected the ability to coordinate multiple texts in the same language. L1 reading comprehension was positively associated with L1 and L2 integrated writing. Cross-language transfer from L1 integrated writing to L2 was also observed with L1 reading comprehension playing a significant role in the transfer. The findings suggest that the ability to write from sources in L2 could capitalize on the ability that have already acquired in L1. This study contributed to existing literature by substantiating the cross-language connection between reading and writing in integrated writing. It also supports the adoption and early implementation of integrative pedagogy of reading and writing to better facilitate the development of L2 integrated writing competence. [ABSTRACT FROM AUTHOR]