Dynamic compactors with parameters that adjust automatically to the condition of the subgrade form the basis for intelligent compaction. Dynamic soil compactors create nonlinear vibrations, and the typical characteristics of these vibrations are taken as the basis for the feedback control system for intelligent compaction. With the model of the machine and the soil as the starting point, the periodic loss of contact between the drum and the subgrade is postulated to be the main nonlinear effect. This nonlinearity leads to near periodic and subharmonic vibration phenomena, and it can bring about unstable drum dynamics. The machine behavior can be investigated with the help of the chaos theory. Feedback control systems for rollers are based on the results from the theory of nonlinear oscillations, and they allow optimal compaction performance thanks to continuous adjustment to the compaction status. Starting with large amplitudes and low frequencies, the automatic control system ensures a good depth effect. As the compaction increases, the frequencies rise and the amplitudes are automatically reduced; those actions lead to optimal surface layer compaction at the end of the process. The soil stiffness measurement, which is performed in parallel with the automatic control, is directly correlated with the plate-bearing test to enable continuous compaction control. In conjunction with a documentation system, intelligent compaction makes it possible to prove the homogeneity and the achieved compaction degree. In the field, intelligent compaction ensures that compaction jobs are completed in a minimum number of passes and allows monitoring of results as work progresses. In addition to optimal compaction with no risk of overcompaction, laboratory costs are reduced and process reliability is maximized.

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The nonlinear vibrations of dynamic soil compactors are taken as the basis for feedback control systems for intelligent compaction. According to the achieved compaction, the parameters of the soil compactor are continuously changed. The vibratory roller measures permanently the stiffness of the subgrade. In conjunction with GPS-data, this measurement can be used as a QA/QC tool. The stiffness data are directly correlated to plate bearing test. In practice, the intelligent compaction ensures that the compaction job is completed in a minimum number of passes, the result is monitored and the compaction energy is automatically adjusted while measuring the soil stiffness.

This chapter focuses on the process of a change in governance in a broader destination region in the mountain tourism sector. A major project involving a complex group of local and regional resort destinations in a key mountain resort area of Switzerland used an approach of governance that included a model with three key aspects: (1) organization and leadership; (2) tasks and resources; and (3) size and dominance. This chapter describes the process of governance in implementing a restructuring and realignment of the many local tourism organizations to address market concerns more effectively through reduced but more focused and more competitive governance structures. In discussing the lessons learned from the case, the authors put forward a number of points for success, which are important in achieving effective governance within complex regional tourist destination structures. These are discussed further in the chapter and include aspects of composition and responsibility sharing, strategic planning, understanding that which drives performance, stakeholder integration and involvement and effective communication, in addition to the fostering of networks and provision of infl uence in destination governance.

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