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The design issues on network architecture and modulation scheme that can be used to implement reliable MIL‐STD‐1773 avionics optical fiber data buses are discussed. Both single‐star and multi‐star architectures are presented to such optical fiber data buses. Several network configurations based on passive and/or active coupling components are also considered, and they are compared in terms of system complexity and reliability. Moreover, three modulation schemes are presented, i.e. partial trilevel Manchester II bi‐phase coding, extended Manchester II bi‐phase coding with beginning‐stopping flags, and pseudo‐four‐ary pulse width modulation, respectively. Their use can feasibly solve the problem associated with fast identification of correct operation states of an active transmitter at the output of optical receivers.

The kindergarten curriculum in mainland China has evolved through four periods and the current reform began in the end of 1980s. The reform aimed to transform kindergarten practice by shaping ideologies including respect for individual child, active learning, and play-based integrated curriculum. This review of research literatures shows that compared with the practice before the reform, many kindergarten teachers organize classrooms in learning centers, provide more play materials, pay time, and freedom for free play, and pay more attention to individuals. But indoor space organized in rice-seedling-bed model, teacher-led group instruction and teacher-controlled interactions are still often observed after three decades of reform efforts; there still exist great variations among kindergartens of different sponsoring bodies and in different regions. The problems resulted from the innate deficiencies of the top-down and value-priority reform, the conflicts between the advocated value and the traditional Chinese culture with emphasis on Ming-Fen, testing, and the value of children for the whole family and nation, and the unequal distribution of public resources decided by the educational institutions. Therefore, the curriculum reform is not a separate endeavor from other social changes, but a comprehensive and systematic change. To guarantee the success of the curriculum reform, the Chinese society needs cultural transformation and institutional reconstruction.