Age‐related macular degeneration (AMD) is one of the main reasons for visual impairment worldwide. The assessment of risk for the development of AMD requires reliable detection and quantitative mapping of retinal abnormalities that are considered as precursors of the disease. Typical signs of the latter are the so‐called drusen that appear as yellowish spots in the retina. Automated detection and segmentation of drusen provide vital information about the severity of the disease. The authors propose a novel method for the detection and segmentation of drusen in colour fundus images. The method combines colour information of the object with its boundary information for the accurate detection and segmentation of drusen. To perform non‐uniform illumination correction and to minimise inter‐subject variability a novel colour normalisation method has been proposed. Experiments are conducted on publicly available STARE and ARIA datasets. The method achieves an overall accuracy of 96.62% which is about 4% higher than the state‐of‐the‐art method. The sensitivity and specificity of the proposed method are 95.96 and 97.64%, respectively.

With the rapid development of information and communication technologies, people are increasingly referring to web information to assist in their travel planning and decision making. Research shows that people conduct collaborative information searches while planning their travel activities online. However, little is known in depth about tourists' online collaborative search. This study examines tourists' collaborative information search behavior in detail, including their search stages, online search strategies, and information flow breakdowns. The data for analysis included pre‐ and postsearch questionnaires, web search and chat logs, and postsearch interviews. A model of tourist collaborative information retrieval was developed. The model identified collaborative planning, collaborative information searching, sharing of information, and collaborative decision making as four stages of tourists' collaborative search. The results show that tourists collaborated by planning their search strategies, dividing search tasks into subtasks and allocating workload, using search queries and URL links recommended by teammates, and discussing search results together. Related personal knowledge and experiences appeared important in trip planning and collaborative information search. During the collaborative search, tourists also encountered various information flow breakdowns in different search stages. These were classified and their effects on collaborative information search were reported. Implications for system design in support of collaborative information retrieval in travel contexts are also discussed.

Users often reformulate or modify their queries when they engage in searching information particularly when the search task is complex and exploratory. This paper investigates query reformulation behavior in collaborative tourism information searching on the Web. A user study was conducted with 17 pairs of participants and each pair worked as a team collaboratively on an exploratory travel search task in two scenarios. We analyzed users' collaborative query (CQ) reformulation behavior in two dimensions: firstly, CQ reformulation strategies; and secondly, the effect of individual queries and chat logs on CQ reformulation. The findings show that individual queries and chat logs were two major sources of query terms in CQ reformulation. The statistical results demonstrate the significant effect of individual queries on CQ reformulation. We also found that five operations were performed to reformulate the CQs, namely: addition, modification, reordering, addition and modification, and addition and reordering. These findings have implications for the design of query suggestions that could be offered to users during searches using collaborative search tools.