Using Markov Chains for link prediction in adaptive web sites

The large number of Web pages on many Web sites has raised navigational problems. Markov chains have recently been used to model user navigational behavior on the World Wide Web (WWW). In this paper, we propose a method for constructing a Markov model of a Web site based on past visitor behavior. We use the Markov model to make link predictions that assist new users to navigate the Web site. An algorithm for transition probability matrix compression has been used to cluster Web pages with similar transition behaviors and compress the transition matrix to an optimal size for efficient probability calculation in link prediction. A maximal forward path method is used to further improve the efficiency of link prediction. Link prediction has been implemented in an online system called ONE (Online Navigation Explorer) to assist users' navigation in the adaptive Web site

'Datafication': Making sense of (big) data in a complex world

This is a pre-print of an article published in European Journal of Information Systems. The definitive publisher-authenticated version is available at the link below. Copyright @ 2013 Operational Research Society Ltd.No abstract available (Editorial

An Editor for Helping Novices to Learn Standard ML

This paper describes a novel editor intended as an aid in the learning of the functional programming language Standard ML. A common technique used by novices is programming by analogy whereby students refer to similar programs that they have written before or have seen in the course literature and use these programs as a basis to write a new program. We present a novel editor for ML which supports programming by analogy by providing a collection of editing commands that transform old programs into new ones. Each command makes changes to an isolated part of the program. These changes are propagated to the rest of the program using analogical techniques. We observed a group of novice ML students to determine the most common programming errors in learning ML and restrict our editor such that it is impossible to commit these errors. In this way, students encounter fewer bugs and so their rate of learning increases. Our editor, C Y NTHIA, has been implemented and is due to be tested on st..

The Impact of Link Suggestions on User Navigation and User Perception

The study reported in this paper explores the effects of providing web users with link suggestions that are relevant to their tasks. Results indicate that link suggestions were positively received. Furthermore, users perceived sites with link suggestions as more usable and themselves as less disoriented. The average task execution time was significantly lower than in the control condition and users appeared to navigate in a more structured manner. Unexpectedly, men took more advantage from link suggestions than women

Investigating people: a qualitative analysis of the search behaviours of open-source intelligence analysts

The Internet and the World Wide Web have become integral parts of the lives of many modern individuals, enabling almost instantaneous communication, sharing and broadcasting of thoughts, feelings and opinions. Much of this information is publicly facing, and as such, it can be utilised in a multitude of online investigations, ranging from employee vetting and credit checking to counter-terrorism and fraud prevention/detection. However, the search needs and behaviours of these investigators are not well documented in the literature. In order to address this gap, an in-depth qualitative study was carried out in cooperation with a leading investigation company. The research contribution is an initial identification of Open-Source Intelligence investigator search behaviours, the procedures and practices that they undertake, along with an overview of the difficulties and challenges that they encounter as part of their domain. This lays the foundation for future research in to the varied domain of Open-Source Intelligence gathering

The future of social is personal: the potential of the personal data store

This chapter argues that technical architectures that facilitate the longitudinal, decentralised and individual-centric personal collection and curation of data will be an important, but partial, response to the pressing problem of the autonomy of the data subject, and the asymmetry of power between the subject and large scale service providers/data consumers. Towards framing the scope and role of such Personal Data Stores (PDSes), the legalistic notion of personal data is examined, and it is argued that a more inclusive, intuitive notion expresses more accurately what individuals require in order to preserve their autonomy in a data-driven world of large aggregators. Six challenges towards realising the PDS vision are set out: the requirement to store data for long periods; the difficulties of managing data for individuals; the need to reconsider the regulatory basis for third-party access to data; the need to comply with international data handling standards; the need to integrate privacy-enhancing technologies; and the need to future-proof data gathering against the evolution of social norms. The open experimental PDS platform INDX is introduced and described, as a means of beginning to address at least some of these six challenges

A computational fluid dynamic investigation of inhomogeneous hydrogen flame acceleration and transition to detonation

Gas explosions in homogeneous reactive mixtures have been widely studied both experimentally and numerically. However, in practice and industrial applications, combustible mixtures are usually inhomogeneous and subject to vertical concentration gradients. Limited studies have been conducted in such context which resulted in limited understanding of the explosion characteristics in such situations. The present numerical investigation aims to study the dynamics of Deflagration to Detonation Transition (DDT) in inhomogeneous hydrogen/air mixtures and examine the effects of obstacle blockage ratio in DDT. VCEFoam, a reactive density-based solver recently assembled by the authors within the frame of OpenFOAM CFD toolbox has been used. VCEFoam uses the Harten–Lax–van Leer–Contact (HLLC) scheme fr the convective fluxes contribution and shock capturing. The solver has been verified by comparing its predictions with the analytical solutions of two classical test cases. For validation, the experimental data of Boeck et al. (1) is used. The experiments were conducted in a rectangular channel the three different blockage ratios and hydrogen concentrations. Comparison is presented between the predicted and measured flame tip velocities. The shaded contours of the predicted temperature and numerical Schlieren (magnitude of density gradient) will be analysed to examine the effects of the blockage ratio on flame acceleration and DDT

Accelerating Agriculture Productivity Improvement in Bangladesh: Mitigation co-benefits of nutrients and water use efficency

Analysis of potential mitigation in the development project Accelerating Agriculture Productivity Improvement (AAPI) in Bangladesh showed a 2% reduction in greenhouse gas (GHG) emissions, driven by urea deep placement (UDP) and alternate wetting and drying (AWD) in flooded rice systems. Given high emissions associated with conventional irrigated rice production, this represents a substantial reduction in emissions. AAPI promotes UDP, a fertilization practice known to increase nitrogen uptake efficiency. Based on the project plan and progress of implementation, UDP adoption was anticipated on 1.1 million ha of aman rice and 700,000 ha of boro rice. UDP is an example of the absolute emission reductions that are possible when a practice is widely implemented. AAPI promotes AWD, an irrigation practice for rice that reduces the amount of water used and results in decreased emissions. AAPI tested AWD on a pilot scale (21,000 ha). Climate change mitigation benefits would increase dramatically if adoption of AWD were more widespread. Due to increased rice yields, UDP and AWD reduce the emission intensity (CO2e emitted per kg production) from rice production by 10–48%

Better Life Alliance in Zambia: Climate change mitigation as a co-benefit of improved landscape, agroforestry, soil, and fertilizer management

Analysis of agricultural activities in the Better Life Alliance (BLA) project in Zambia showed potential reduction in greenhouse gas emissions (GHG), mostly (85%) due to avoided savanna degradation and conversion. The GHG impact due to BLA’s interventions is estimated at –902,531 tCO2e/yr, equivalent to saving 2,089,550 barrels of oil. BLA’s business model linked prevention of degradation and conversion of shrubland to market-based incentives for agricultural crops, thereby providing farmers with economic incentives for conservation and climate change mitigation. BLA promoted a comprehensive approach to soil fertility management. It promoted agroecological approaches such as recycling farm organic resources, planting nitrogen-fixing trees, minimal tillage, and cover crops. BLA reduced postharvest loss (PHL) through improved product processing, storage, and packaging. Changes in PHL were estimated for groundnuts (–100%), maize (–40%), rice (–80%), and soybeans (–67%), which contributed to decreases in emission intensity (GHG emissions per unit of production) for each of these products