In this paper, we investigate the attitude tracking problem of uncertain flexible spacecraft systems subject to external disturbances. In sharp contrast to existing results, the dynamics of flexible spacecraft systems and external disturbances are allowed to be unknown. To deal with the challenges by these unknown factors, we develop a class of nonlinear internal models which converts the attitude tracking problem of uncertain flexible spacecraft systems into a regulation problem of an augmented system. Furthermore, to overcome the difficulties caused by the unmeasurable modal variable, the uncertainty introduced by the internal model, and the cross-coupling of the uncertainties with the system state, we design an auxiliary dynamic system for auxiliary stabilization, a dynamic compensator for dynamic compensation, and a linearly parameterized transformation for adaptive regulation in sequence. By introducing a series of coordinate and input transformations, we propose an adaptive dynamic control law to achieve regulation of the augmented system and thus leading to the solution to the attitude tracking problem. In addition, we analyze the convergence issue of the estimated parameter to its true value by the persistently exciting condition. Finally, the effectiveness of the developed approach is verified by its application to the attitude manoeuvre of a flexible spacecraft system in the presence of external disturbances.

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This article examines different types of queer spaces in contemporary Shanghai together with the various same-sex subjects that inhabit these spaces. In doing so, it discusses the impact of transnational capitalism, the nation state and local histories on the construction of urban spaces and identities. Combining queer studies and urban ethnography, this article points to the increasing social inequalities hidden behind the notion of urban cosmopolitanism created by the deterritorializing and meanwhile territorializing forces of transnational capital and the state. It also sheds light on how these various identities and spaces are lived and experienced by ordinary people, as well as possible ways of resistance to the dominant narratives

Although homosexuality was decriminalised in 1997 and partially depathologised in 2001, LGBTQ issues are still strictly censored in the Chinese media. With the rapid growth of China's LGBTQ community, an increasing number of independent films featuring LGBTQ issues have emerged in the past two decades. In this article, I trace a brief history of queer cinema in the People's Republic of China in the postsocialist era (1978 to present). In particular, I chart the significant turn from 'celluloid comrades', i.e. queer people being represented by heterosexual identified filmmakers in an ambiguous way, to what leading Chinese queer filmmaker Cui Zi'en calls 'digital video activism', in which LGBTQ individuals and groups have picked up cameras and made films about their own lives. In doing so, I unravel the politics of representation, the dynamics of mediated queer politics and the political potential of queer filmmaking in China. I suggest that in a country where public expressions of sexualities and demands for sexual rights are not possible, queer filmmaking has become an important form of queer activism that constantly negotiates with government censorship and the market force of commercialisation. Rather than representing a pre-existing identity and community, queer films and filmmaking practices have brought Chinese gay identities and communities into existence.

In this article, I chart a brief history of the queer community documentary in the PRC since the 2000s by introducing its historical conditions of emergence and development. In doing so, I highlight the activist dimension of queer filmmaking and its transnational nature. I focus specifically on the aesthetics and politics, together with modes of production and circulation, of these queer community documentaries. I call the group of filmmakers working around the Beijing Queer Film Festival and the China Queer Film Festival Tour the 'queer generation'.The 'queer generation' filmmakers use documentary films as a tool to engage in political and social activism. Their films and activist practices should be put in a transnational context and seen as part of the transnational cinema and international queer movements. As these filmmakers documented queer community histories, they also 'queered' Chinese documentaries and Chinese film industries at large. Their works represent grassroots, community-based and activist-oriented political engagements in contemporary China; these works also point to the political potential of queerness and documentary films in the world today.