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This thesis offers an ethnographic account of how art cinema culture is produced in China since the turn of twenty-first century. With an underdeveloped art cinema infrastructure and the endurance of forceful Party-state control over public cinematic spaces, there have emerged numerous individuals and organisations taking part in circulating the information and appreciation of the art of film through a number of different alternative paths and networks. This thesis scrutinises the role of the intermediary practitioners - particularly those involved in independent exhibition, internet criticism and underground distribution - and how they think about cinema, negotiate judgement and appreciation, and construct a discourse of value and taste. It is argued that, although their motivation was derived from a cinephilia seeking to forge an alternative mode of distribution and reception, the 'new' cinema culture they have produced simultaneously negotiates a subtly complicit relationship with authoritative and market forces. Their cultural practices and engagement oscillates between the status of independence and autonomy, a rejection of cultural homogeneity and monopolisation, and culture as promotion that accrues a public image and recognition. Moreover, involved in diversified practices and taste formation, the intermediary practitioners have also sought to produce a new form of legitimacy in reference to cultural value and judgement. To attain their legitimacy, they have sought to constitute a coordinated and interrelated network in the site of art cinema. The network is manifested - its mode of operation explicitly - as part of the art film culture in a way that represents the larger spectrum of socio-cultural hierarchy in contemporary Chinese culture and society.

An active scalar system refers to a system with a scalar field that is coupled to the fluid dynamics and gives feedback to the velocity field through local forces. Active scalar turbulence systems are ubiquitous, and the study of these systems is a central focus of research in theoretical plasma physics. As examples, the 2D Cahn-Hilliard Navier-Stokes (CHNS) system and 2D Magnetohydrodynamics (MHD) system are studied in this dissertation. The similarities and differences between 2D CHNS and 2D MHD are discussed. These are both elastic (i.e., self-restoring) systems, and display a memory, governed by freezing-in laws. The CHNS system supports an elastic wave, which is analogous to Alfven wave in MHD. Cascades and spectra in 2D CHNS are investigated, with focus on the interaction between inverse and forward cascades. The inverse cascade of mean square concentration $\langle\psi^2\rangle$, which is closely related to the real space dynamics of blob formation and merger, is found to be the dominant nonlinear transfer process. The spectrum of $\langle\psi^2\rangle_k$ exhibits a scaling law of $\sim k^{-7/3}$, and this exponent is the same as the corresponding one in 2D MHD. On the other hand, the kinetic energy spectrum follows $E_k\sim k^{-3}$. This exponent is closer to that for 2D Navier-Stokes, instead of that for 2D MHD. We suggest this is because the restoring force is significant only in the interfacial regions. The packing fraction of interfacial regions is small because of the formation and merger of blobs.This suggests that the inverse cascade of $\langle \psi^2 \rangle$ - related to blob coalescence - modifies the forward cascade in 2D CHNS.The evolution of the concentration field of the Cahn-Hilliard system in the background of a single eddy is studied. This is analogous to the flux expulsion phenomenon in 2D MHD. Though the system is simple, complex evolution is observed. 3 stages are observed: the ``jelly roll'' pattern stage, the stage of topological evolution, and the ``target'' pattern stage. The target pattern is metastable, as the bands gradually merge with time. We also study turbulent transport in active scalar systems. We intended to first explore the classic problem of the suppression of turbulent transport in 2D MHD as an exercise in code verification, and then move to 2D CHNS. However, novel blob-and-barrier real space structures were observed with higher magnetic Reynolds number $\mathrm{Rm}$ in 2D MHD. We argue that the conventional approach of mean field theory is not applicable for the case without an external large scale magnetic field. The magnetic energy is observed to be concentrated in the intermittent, thin transport barrier regions, which located in the interstices between blobs of magnetic potential. The turbulent transport is quenched primarily because of these barriers. Barrier formation is linked to the inverse cascade of mean square magnetic potential $\langle A^2\rangle$ and negative turbulent resistivity. For small scale forcing, spontaneous formation of layering occurs.More generally, we demonstrate that synergistic studies of related but different systems -- 2D CHNS and 2D MHD -- can lead to improved understanding. These studies can provide insights for all active scalar turbulence systems, since these systems share important common properties such as memory, elastic waves, and conservation laws.

Smart materials exhibit nonlinearities and hysteresis when driven at field levels necessary to meet stringent performance criteria in high performance applications. This requires models and control designs that effectively compensate for the nonlinear, hysteretic field-coupled material behavior. In this dissertation, we investigate model identification using the homogenized energy model and adaptive control of hysteresis in smart hysteretic system, while the approaches are applicable to control of a wide class of ferroelectric, ferromagnetic and ferroelastic materials, we illustrate the ideas through the example of controlling a ferroelectric actuator. We pursue the problem of hysteresis control through two complimentary approaches: linear adaptive control using an inverse compensator and nonlinear adaptive control. Inverse control is a fundamental approach to accommodate hysteresis effect by constructing a right inverse of the hysteresis. Due to the open-loop nature of inverse control, the performance of the inverse compensation is susceptible to model uncertainties and to error introduced by inexact inverse algorithms. The objective of adaptive control is to design a controller that can adjust its behavior to tolerate uncertainties or time-varying parameters. We employ the homogenized energy model to quantify the hysteresis. On the basis of the hysteresis model, we propose an adaptive control framework by combining inverse compensation with adaptive control techniques, and investigate the parameter identification methods for the hysteresis model. We prove the asymptotic tracking property of the proposed adaptive inverse control algorithm, discuss the issue of parameters convergence and illustrate the performance of the proposed control method through simulations. Adaptive nonlinear control is a more challenging task and has received increasing attention in recent years. The challenge addressed here is how to fuse hysteresis models with available adaptive control techniques to have the basic requirement of stability of the system. In this dissertation, an adaptive variable structure control approach, serving as an illustration, is fused with the homogenized energy model without constructing a hysteresis inverse. The global stability of the system and tracking a desire trajectory to a certain precision are achieved under certain conditions. Simulations are performed on an unstable nonlinear system. The purpose of exploring new avenues to fuse the model of hysteresis nonlinearities with the available adaptive controller designs without constructing a hysteresis inverse is achieved and illustrated with the promising simulation results. This provides a step toward the development of a general nonlinear adaptive control framework for hysteretic systems.