Chew Hung Chang

The relationship between height to width ratios and the heat island intensity at 22:00 h for Singapore

The statistical relationship between urban canyon height-to-width (H/W) ratios and nocturnal heat island intensities for public housing estates in Singapore has been examined. Although a number of similar studies have been conducted for temperate cities, this is a first attempt at correlating H/W to heat island intensities for a tropical city. Heat island intensities were examined specifically at 22:00 h because a previous study of Singapores heat island determined that the heat islands were well developed by that time. A total of 17 Housing Development Board (HDB) estates were studied and at least two vehicle traverses were conducted for each estate on nights with a few days of antecedent dry weather conditions. H/W ratios for each estate were tabulated by proportion of building length. The statistical analysis demonstrates that there is a positive relationship between the heat island intensities and the median H/W, such that ΔTu−r(max)=0.952 (median H/W)−0.021, statistically significant at α=0.05 with a p-value of 0.001 and a correlation coefficient of 0.53. Copyright

Mobile G-Portal supporting collaborative sharing and learning in geography fieldwork: an empirical study

Integrated with G-Portal, a Web-based geospatial digital library of geography resources, this paper describes the implementation of Mobile G-Portal, a group of mobile devices as learning assistant tools supporting collaborative sharing and learning for geography fieldwork. Based on a modified Technology Acceptance Model and a Task-Technology Fit model, an initial study with Mobile G-Portal was conducted involving 39 students in a local secondary school. The findings suggested positive indication of acceptance of Mobile G-Portal for geography fieldwork. The paper concludes with a discussion on technological challenges, recommendations for refinement of Mobile G-Portal, and design implications in general for digital libraries and personal digital assistants supporting mobile learning.

PBL-GIS in Secondary Geography Education: Does It Result in Higher-Order Learning Outcomes?.

Abstract This article presents research on evaluating problem-based learning using GIS technology in a Singapore secondary school. A quasi-experimental research design was carried to test the PBL pedagogy (PBL-GIS) with an experimental group of students and compare their learning outcomes with a control group who were exposed to PBL but not GIS. The results show significant differences in the learning outcomes between the two groups. Specifically, students in the control group show more memorization skill while students in the experimental group demonstrate more analytical and evaluation skills. The conclusion is that learning with PBL-GIS pedagogy can result in higher-order learning outcomes.

Lessons from learner experiences in a field-based inquiry in geography using mobile devices

Geographical inquiry involves collecting, using and making sense of the data to investigate some geographical phenomena. With the increasing number of mobile devices equipped with Internet access capabilities, there is a wide scope for using it in field inquiry where learning can take place in the form of social interactions between team members while performing a common task. The authors examine the use of MobiTOP (Mobile Tagging of Objects and People), a geospatial digital library system which allows users to contribute and share multimedia annotations via mobile devices, within a geographical field inquiry. A key feature of MobiTOP that is well suited for collaborative learning is that annotations are hierarchical, allowing annotations to be annotated by other users to an arbitrary depth. A group of student and teachers involved in an inquiry-based learning activity in geography was instructed to identify rock types and associated landforms by collaborating with each other using the MobiTOP system. A method combining several data collection methods was used. Four main findings on the affordances of the mobile phone, the need for specialized training in using the application with the mobile phone, design considerations of the application and the authentic context of learning with fieldwork are reported. A discussion on the implication of these findings and how mobile technology may be used for geographical field learning are also included in this paper.

Exploring Hierarchically Organized Georeferenced Multimedia Annotations in the MobiTOP System

We introduce MobiTOP, a map-based interface for accessing hierarchically organized georeferenced annotations. Each annotation contains multimedia content associated with a location, and users are able to annotate existing annotations, in effect creating a hierarchy. MobiTOP’s interface was designed using a participatory design methodology to ensure that the user interface meets the needs of potential users. A pilot study to compare the MobiTOP interface with a space-filling thumbnail (SFT) interface suggested that participants preferred the MobiTOP design for accessing annotations even though the SFT interface was conceptually easier to understand resources.

Sharing Mobile Multimedia Annotations to Support Inquiry-Based Learning Using MobiTOP

Mobile devices used in educational settings are usually employed within a collaborative learning activity in which learning takes place in the form of social interactions between team members while performing a shared task. We introduce MobiTOP (Mobile Tagging of Objects and People), a geospatial digital library system which allows users to contribute and share multimedia annotations via mobile devices. A key feature of MobiTOP that is well suited for collaborative learning is that annotations are hierarchical, allowing annotations to be annotated by other users to an arbitrary depth. A group of student-teachers involved in an inquiry-based learning activity in geography were instructed to identify rock types and associated landforms by collaborating with each other using the MobiTOP system. The outcome of the study and its implications are reported in this paper.

Social navigation in digital libraries by bookmarking

In the age of Web 2.0, users are increasingly familar with social tagging or bookmarking where comments and ratings are added by users to objects on the web for public consumption. Such comments and ratings are represented in bookmarks which can be used for information or opinion sharing, user interest discovery, and content recommendation. In this paper, we investigate social bookmarking in digital libraries and derive the design requirements for digital library incorporating social bookmarking. Instead of implementing social bookmarking functions in digital library systems from ground zero, we have chosen to explore the possibilities of integrating pre-existing digital library systems with preexisting social bookmarking systems, and to derive a feasible system architectural design. We also present a case study where G-Portal, a geography digital library system, is integrated with Scuttle, an open source social bookmarking system.

Singapore students' misconceptions of climate change

Climate change is an important theme in the investigation of human–environment interactions in geographic education. This study explored the nature of students’ understanding of concepts and processes related to climate change. Through semi-structured interviews, data was collected from 27 Secondary 3 (Grade 9) students from Singapore. The data was subjected to thematic analysis using Chi and Roscoes conceptual change framework. The results showed that the students’ base knowledge of climate change is composed of incomplete and incorrect elements built within coherent and structurally sound mental models. Due to the consistency of the models in expanding the logic, albeit erroneous, of explaining the climate change conundrum, it is posited that students are unaware of mistakes inherent in their judgements. Transformation of these mental models through multiple and deliberate refutations should be foremost in a geography teachers pedagogical approach.

Supporting field study with personalized project spaces in a geographical digital library

Digital libraries have been rather successful in supporting learning activities by providing learners with access to information and knowledge. However, this level of support is passive to learners and interactive and collaborative learning cannot be easily achieved. In this paper, we study how digital libraries could be extended to serve a more active role in collaborative learning activities. We focus on developing new services to support a common type of learning activity, field study, in a geospatial context. We propose the concept of personal project space that allows individuals to work in their personalized environment with a mix of private and public data and at the same time to share part of the data with team members. To support the portability of the resources in our digital library, the selected resources can be exported in an organized manner.

TagNSearch: Searching and Navigating Geo-referenced Collections of Photographs

TagNSearch is a map-based tool for searching and browsing geo-tagged photographs based on their associated tags. Using Flickr as the dataset, TagNSearch returns, for a given query, photographs clustered by locations, and summarizes each cluster of photographs by cluster-specific tags. A map-based interface is also provided to help users better search, navigate and browse photographs and their clusters. A qualitative evaluation comparing TagNSearch and an existing tag search support in Flickr was also conducted. The task involved finding locations associated with a set of photographs. Participants were found to perform this task better using TagNSearch than Flickr.