Siu Man Lui

Geographic Forwarding and Routing for Ad-hoc Wireless Network: A Survey

Routing for ad-hoc wireless network is challenging, and there is no single routing strategy to deal with the complex and dynamic nature of the ad-hoc network. Given the availability of the low cost of location-aware devices, geographic forwarding and routing provided opportunity for improving existing ad-hoc routing strategies. In this paper, geographic forwarding strategies and geographic routing protocols are reviewed; challenges of implementing geographic routing in ad-hoc network are identified and discussed. More research effort is called for improving the basic forwarding strategy to increase the efficiency of the geographic routing protocol to provide a practical solution addressing the issues related to routing around local minima.

Quantifying the costs and benefits of privacy-preserving health data publishing

Cost-benefit analysis is a prerequisite for making good business decisions. In the business environment, companies intend to make profit from maximizing information utility of published data while having an obligation to protect individual privacy. In this paper, we quantify the trade-off between privacy and data utility in health data publishing in terms of monetary value. We propose an analytical cost model that can help health information custodians (HICs) make better decisions about sharing person-specific health data with other parties. We examine relevant cost factors associated with the value of anonymized data and the possible damage cost due to potential privacy breaches. Our model guides an HIC to find the optimal value of publishing health data and could be utilized for both perturbative and non-perturbative anonymization techniques. We show that our approach can identify the optimal value for different privacy models, including K-anonymity, LKC-privacy, and ∊-differential privacy, under various anonymization algorithms and privacy parameters through extensive experiments on real-life data.

Individual Privacy and Organizational Privacy in Business Analytics

The use of business analytics to reveal useful information from transactional and operational databases involves accessing private information of both individuals and organizations. This practice has raised the privacy concern of individuals and policy makers. In this paper, we propose a privacy preserving approach for business analytics based on keyed bloom filters. We illustrate this approach using market basket analysis, and then evaluate its performance using real datasets from a point-of-sale and Web clickstream. The major advantage of this approach is the positive relationship for the level of privacy security and analysis precision. In other words, the tradeoff of the level of privacy protection for our solution is data storage space; whereas for other existing methods, there is always a tradeoff between analysis precision and the level of privacy protection

Effects of Smiling and Gender on Trust Toward a Recommendation Agent

This study seeks to determine whether a recommendation agent’s smile and gender affect users’ trust toward the agent. We also investigate gender differences in trust toward recommendation agents of different genders and facial expressions. We present findings from a 2x2 experiment (male vs. female and smiling vs. non-smiling agents). In the context of laptop shopping, we found that on average smiling agents are perceived to be more competent than non-smiling agents and male agents are perceived to be more competent than female agents. There is a significant interaction effect between an agents smile and gender on trust in benevolence. Specifically, male subjects tend to believe that smiling agents are more competent than non-smiling agents, while female subjects are less sensitive to the agent’s smile. Interestingly, female subjects perceive male agents to be more competent than female agents, while male subjects are almost indifferent toward the agent’s gender. Among the female subjects, trust in benevolence is highest toward a smiling male agent. Our results suggest that the gender and facial expressions of a recommendation agent should be considered when designing a virtual salesperson for online stores.

Information Reuse among Government Websites in Asian Countries

This paper studied the government Websites of 47 member nations of the United Nations in Asia. To investigate the extent of information availability and information reuse among these websites, data on number of pages, number of pages receiving incoming hyperlinks and number of pages containing outgoing hyperlinks of the government websites of each nation were gathered from major commercial search engines. The correlations of information availability and reuse with economics indicators, information technology advancement indicators, and democracy level indicators of these nations were examined. We further analyzed the information reuse within the government Websites by examining the hyperlinks interlinking among the Websites of all selected nations. We considered these government Websites as a hyperlinked network and used network analysis and visualization techniques to analyze and visualize the network structure. The results identified the role and significance of each nation in this government information network.

Low resolution grid mapping approach for geographic routing

Handling local minima in geographical routing is of great importance since it is a core component in geographic forwarding processes. This paper proposes a new low-resolution grid occupancy mapping GOM approach to effectively handle local minima for existing geographic routing protocols. The proposed approach seeks to discover and distribute a low-resolution map containing anomalies in the coverage areas where potential local minima exist. This approach minimises overhead while maintaining minimal global knowledge to effectively route around local minima. Experimental results demonstrate significantly lower probe bandwidth and memory requirements in comparison to the previously proposed boundary mapping protocol BMP at the cost of an increase in hello message size. The proposed approach is well suited for scalable and dynamic mobile networks due to the reduction in probe and memory overhead and cellular structure. Future research includes improvements to the boundary detection algorithm and integration into existing geographic routing protocols.

Relationship of blink, affect, and usability of graph reading tasks

Dynamic graphs that represent a great deal of time-series data have become increasingly common these days. Although previous research revealed that blink facilitates visual search tasks by attracting human attention, blink features have not been clearly evident in a dynamic graph reading context. This study examines the effects of blink on the users affective experience and usability of using a blinking line graph. Additionally, this study describes the empirical experiment setup for investigating the characteristics of task types as a moderator to the relationship between blink and the users experience. This research aims (1) to theoretically contribute graph comprehension domain by investigating the effects of blink on a graph comprehension process, (2) to design a quantitative experiment and to propose possible hypotheses, and (3) to understand the influence of task types on reading of a blinking graph.