Combining the evidence of different relevance feedback methods for information retrieval

It has been known that retrieval effectiveness can be significantly improved by combining multiple evidence from different query or document representations, or multiple retrieval techniques. In this paper, we combine multiple evidence from different relevance feedback methods, and investigate various aspects of the combination. We first generate multiple query vectors for a given information problem in a fully automatic way by expanding an initial query vector with various relevance feedback methods. We then perform retrieval runs for the multiple query vectors, and combine the retrieval results. Experimental results show that combining the evidence of different relevance feedback methods can lead to substantial improvements of retrieval effectiveness.     

Microfluidic fabrication of water-in-water (w/w) jets and emulsions

We demonstrate the generation of water-in-water (w/w) jets and emulsions by combining droplet microfluidics and aqueous two-phase systems (ATPS). The application of ATPS in microfluidics has been hampered by the low interfacial tension between typical aqueous phases. The low tension makes it difficult to form w/w droplets with conventional droplet microfluidic approaches. We show that by mechanically perturbing a stable w/w jet, w/w emulsions can be prepared in a controlled and reproducible fashion. We also characterize the encapsulation ability of w/w emulsions and demonstrate that their encapsulation efficiency can be significantly enhanced by inducing formation of precipitates and gels at the w/w interfaces. Our work suggests a biologically and environmentally friendly platform for droplet microfluidics and establishes the potential of w/w droplet microfluidics for encapsulation-related applications.     

Gender differences in instrumental learning among secondary school students in Hong Kong

This paper examines the extent of gender differences, and discusses the role of gender in musical instrument learning. It focuses on the collective instrumental experiences of 1493 Chinese students (774 boys and 719 girls attending grades 7–13) within Western and non‐Western musical traditions in Hong Kong. The discussion draws attention to gender differences in the learning of Chinese and Western musical instruments, in musical interest and instrumental learning, and in the reasons why students learn or do not learn musical instruments. The paper argues that, while female and male students exhibit different attitudes towards the types of instruments learnt, significant correlations exist between their interest in music and parental support for their instrumental learning. Gender is brought to the fore by the pedagogical actions of the teacher, the mass media and by parental efforts to reduce gender bias and stereotypes through school, public and family education.     

The Follow-Up Studies Project: A Brief Report

Studies following up on student teachers who have started full-time teaching constitute part of the programme evaluation scheme at the Institute of Education. Since 1982 two surveys have been conducted to find out the perceptions that former Certificate and Diploma students had of their training programmes and whether there was any noticeable shift in their views about teaching.     

中国龙胆属植物研究（1）

The present paper is the first report of my work in the Flora Reipublicae Popularis Sinicae (Vol. 62, Gentianaceae).       Eight new species and 1 new variety are described from Xizang (Tibet) (4 sp. 1 var.), Yunnan (1 sp.) Sichuan (3 sp.), Qinghai (1 sp.) and Gansu (1 sp.).     

Using phenomenography to investigate the enacted object of learning in teaching activities: the case of teaching Chinese characters in Hong Kong preschools

This study set out to use phenomenography as a theoretical framework to investigate teaching in classrooms, focusing on how the same content is enacted differently in different teaching activities. We observed teaching activities intended to teach children to recognize Chinese characters in preschools and collected data about the delivery of the teaching activities. A total of 3 categories of teaching activities were identified from the data, which correspondingly reflected 3 ways of seeing the recognition of characters: (A) recognition as matching items, (B) recognition as imitating behaviors, and (C) recognition as constructing meanings. Our results were useful for fostering the professional learning of teachers in practical ways as well as holding the potential to further advance the methodology of phenomenography.