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Brown coal is a complex geo material that has significantly different behaviour to rocks with regard to how it changes over time and with changes to in situ stress and environmental conditions. Boreholes in brown coal formations are susceptible to in situ radial deformation of the borehole and these changes may have a negative impact on instrumentation installed in monitoring boreholes as the inner walls squeeze the instruments in the radial direction. The data collected by sensors affected by borehole deformations over time may not be completely consistent with the actual long-term in situ properties of the coal. Mining operations near boreholes in brown coal tend to reduce the in situ stresses and this change may contribute to accelerated deformation or collapse of the borehole. Major time dependent changes can also occur in brown coal in the form of mineral creep and creeping from dissipation of micro-pore gas, resulting into movements of joints/micro fractures in the coal matrix. Internal micro-cracking is promoted by the high pressure of entrapped gas present in the micro pores in brown coal matrix at different stages of loading and unloading. Such additional creeping in conjunction with the mechanical creep, leads to unusually high and unpredictable time dependent deformation patterns in the coal mass. Prolonged exposure to oxygen and slow release of internal gas from exposed coal surfaces (for example the inner walls of a borehole) also alter the chemical as well as engineering properties of brown coal, causing further problems in predicting its geotechnical behaviour. These critical time dependent characteristics of brown coal have received minimal attention in the past. The presented paper attempts to highlight these issues of brown coal behaviour and demonstrates the impact of changes in stress regime due to an approaching mine batter near a borehole in brown coal.

One of the limiting factors in mobile applications development is the restrictions imposed on the user interface through reliance on the standard ITU-T keyboard which is only really optimal for dialling phone numbers. However, with the convergence of the mobile phone with other sensing technologies, such as Radio Frequency Identi.cation (RFID) and the associated Near Field Communications (NFC), Cameras, and 3D motion sensors, we have the opportunity to use new relational interfaces based on touch, vision, and movement to create new and exciting experiences for mobile application users. In this chapter we present the technologies and the software Application Program Interfaces (APIs) associated with these sensors together with methodologies for their use.

Mobile games are expected to play significant role in future mobile services by evolving beyond the largely single player titles that currently dominate the market to ones that take advantage expanding mobile phone functionality and the wide demographic of the mobile phone user. However, because of the fragmented nature of the mobile software development market, and the restrictions imposed by the mobile phone hardware, the skills required for games development are more akin to embedded software development and those used in the game development of the early 1980s, rather than those currently practiced amongst console and PC game developers. In the first half of this chapter we discuss the hardware restrictions and the different software environments encountered together with methodologies so that mobile game developers can produce effective designs. Having discussed the challenges in developing mobile games in the second half of the chapter we discuss the opportunities for innovation provided by the mobile phones through both their anywhere connectivity and the ever enhancing feature set. To this end we present examples using Cameras, RFID, Bluetooth, and GPS that illustrate how through careful design mobile games do not simply have to be cut down versions of console games but can provide uniquely mobile gaming experiences.