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The propeller cavitation not only affects the propulsive efficiency of a ship but also can cause vibration and noise. Accurate predictions of propeller cavitation are crucial at the design stage. This paper investigates the feasibility of the Reynolds-averaged Navier–Stokes (RANS) method in predicting propeller cavitation in behind-hull conditions, focusing on four aspects: (i) grid sensitivity; (ii) the time step effect; (iii) the turbulence model effect; and (iv) ability to rank two slightly different propellers. The Schnerr-Sauer model is adopted as the cavitation model. A model test is conducted to validate the numerical results. Good agreement on the cavitation pattern is obtained between the model test and computational fluid dynamics. Two propellers are computed, which have similar geometry but slightly different pitch ratios. The results show that RANS is capable of correctly differentiating the cavitation patterns between the two propellers in terms of the occurrence of face cavitation and the extent of sheet cavitation; moreover, time step size is found to slightly affect sheet cavitation and has a significant impact on the survival of the tip vortex cavitation. It is also observed that grid refinement is crucial for capturing tip vortex cavitation and the two-equation turbulence models used – realizable k-ε and shear stress transport (SST) k-ω – yield similar cavitation results.

The characteristic of hull wake for a ship operating in oblique flow significantly affects the ship performance at off-design conditions. This paper presents a numerical study on the hull wakes under oblique flow conditions and analyzes the scale effect. RANS method combined with SST k-ω turbulence model is adopted and an international benchmark ship, Japan Bulk Carrier (JBC), is computed. Drift angles ranging from 0° to 20° with an interval of 5° are considered. Results show that the oblique flow considerably changes the hull wake field. Unlike a left-right symmetric pattern at zero drift angle, the nominal wake in oblique flow conditions shows a strong asymmetry since the flow at the windward side is close to the incoming flow whereas the flow at the leeward side is featured by the vortices detached from the hull. It is also revealed that the mean wake fraction decreases as the drift angle increases. Both model and full scales are simulated and the comparison between them shows significant differences in the wake pattern on the leeward side and the magnitude of the mean wake fraction. Compared with the model scale, the full scale has a stronger aft-body vortex and a smaller mean wake fraction.

Reduction and coalescence for carboxylate-capped Ag nanoparticles can be achieved in several minutes by soaking the nanoparticle deposits in ascorbic acid aqueous solution. The reduced deposits exhibit a low electrical resistivity in the same order as with bulk Ag. The effect of the chain length of the carboxylates and the kinetics of particle coalescence were explored in this study. Bendable conductive films can be fabricated on a PDMS substrate using this low temperature chemical reduction method.

Eletrochemical corrosion properties of Cu and Ag in the aqueous solutions of reducing agents of formic acid, glycol and ascorbic acid with various concentrations were examined respectively. Experimental results show that there exists no passivation stage on the polarization curves of Cu and Ag in those reductive solutions. Ascorbic acid corrodes Ag faster than the otherss, while formic acid is most corrosive for Cu. Ethylene glycol doesn't cause serious corrosion for Ag and Cu.

Against current privileging of diasporic identity as the (trans)migrants’ challenge to the normativity of national identity and belonging, this paper considers the case of contract migrant domestic workers in Hong Kong to explore the critical potential of diasporic identification in challenging hegemonic national discourses outside much-discussed European and American contexts. While acknowledging the transnational connections and linkages migrant domestic workers in Hong Kong maintain with their home communities, the paper argues the significance of attending to the simultaneous importance of forgetting in their own understanding and representation of their situation. In light of the common refrain of forgetting observed among these migrant women, the paper elucidates the politics of diasporic identification in their situation, especially the dependence of diasporic identification on consolidating national identity and allegiance through the mediation of gendered norms of family duties.

Discussions of Hong Kong's human rights situation tend to focus on the ex-colony's struggle to protect civil and political rights against the encroachment of the Chinese state. Without contradicting the well-grounded concern with Hong Kong's human rights future articulated in these discussions, this article offers a complementary narrative of human rights development in post-1997 Hong Kong that looks beyond the national frame of such discussions. Drawing attention to Hong Kong's position as a regional centre in the struggle for human rights in Asia under globalisation, the article argues that the activities of local and transnational human rights advocacy groups in the city show positive and promising possibilities of coalitional solidarity on the ground of human rights. Notably, the protests against national security legislation opened up opportunities of articulating diverse struggles for the rights of various social groups, including migrant groups, with the local struggle for civil and politi...

This article seeks to articulate the Third World in/and cultural studies through a critical interrogation and refiguration of the term with reference to the current condition of global capitalism and its structuring effects on collective struggles. Tracing critiques of the term to the historical connection between the Third World and the nation-form, the article suggests a deterritorialization of the Third World to reclaim its relevance under global capitalism as a discursive site of utopian longings for unity among the oppressed and the creation of alternative futures. The deterritorialized Third World is refigured through a theoretical deployment of `queering' and discussed with reference to the experiences of Filipina domestic workers in Hong Kong.

Ōe's Man'en gannen no futtobōru is a powerful national allegory which affords serious meditation on the difficulties and perils of translating and transcribing the desires for collectivity and national identity in modernity. This essay analyzes the novel's attempt to weave the marginalized indigenous and the hegemonic Western into a ‘unique’ Japanese national identity. The narrative resolution of the identity crisisreveals a reinscription of exclusionary racial conceptualizations and elision of Japan's history of capitalist exploitation both within and outside of its national boundaries.

conventional dismissal of women's writings for their supposed inability to transcend personal experiences and concerns, this paper shows how Yu's narrative integrates public testimony into a personal story of love and makes radical use of personal experiences to effect political intervention and interrogate and reconstitute the public. With close attention to the textual (re)negotiation of the dominant personal-public relation in Winter's Tale, it also questions the common feminist reclamation of women's personal narratives through an insistent affirmation of the female subject, and argues for the need to appreciate the diversity of feminist import in women's personal narratives. Rather than the autobiographical validation of subjectivity, Yu's narrative affords critical reflection on the relation between subject constitution, representation of experiences, and knowledge production that problematizes the assump

5W iith increasing institutional acceptance, postcolonial discourse has become a privileged locus of voices of difference, opposition, and resistance. Yet the limitations and biases of the postcolonial perspective have also been persuasively argued in various critical studies. From general reflections on the political implications of deploying a singular term "postcolonial" to designate complex issues of continuities and discontinuities in relations of power and domination under and after colonialism (McClintock; Shohat), the critique has recently been brought closer to home to focus on the relation between the postcolonial perspective and intellectual formation under global capitalism. With reference to the eminent "diasporic" postcolonial theorists holding positions in the prestigious First World academy, Arif Dirlik calls postcoloniality "the condition of the intelligentsia of global capitalism" who, heady with "newfound power," project their post-foundational subjectivities and epistemologies onto the world (356). This claim parallels, with significant difference, Kwame Anthony Appiah's earlier "ungenerous" identification of postcoloniality in the African context