Resonance properties and microstructure of ultracompliant metallic nanoelectromechanical systems resonators synthesized from Al-32 at. % Mo amorphous-nanocrystalline metallic composites

This study details the resonance properties of 20 nm thick nanoelectromechanical system scale cantilevers fabricated from a metallic Al-32 at. %Mo nanocomposite. The advantage of the Al-32 at. %Mo alloy is that its strength and near-atomic surface smoothness enable fabrication of single-anchored metallic cantilevers with extreme length-to-thickness ratios, as high as 400:1. This yields uniquely compliant structures with exquisite force sensitivity. For example, an 8 ??m long, 20 nm thick Al-32 at. %Mo device has a spring constant of K280 ??Nm. We show through transmission electron microscope analysis and continuum modeling that the relevant damping mechanisms are related to the device microstructure.open3

Adaptation to flooding in low‐income urban settlements in the least developed countries: A systems approach

This study aims to use a whole systems approach (1) to understand the processes of adaptation to flooding of the urban poor; (2) to identify new knowledge of how low‐income settlements might better adapt to climatic risks; and (3) to begin to develop appropriate guidance on this. Low‐income urban settlements in the least developed countries (LDCs) present an extreme case where catastrophic natural hazards and chronic social hazards overlap. These low‐income urban populations face the greatest adaptation challenges as they often occupy informal settlements that are particularly exposed to hazards, and have multiple vulnerabilities arising from their lack of basic services. There is a dynamic complexity of issues arising from the many levels of actor involved and multiple social and physical factors. Analysing such a complex phenomenon calls for a specific conceptual framing, and a systems theory approach is suggested to provide a holistic perspective. The case study for this research is located in Dhaka East, where there is both high vulnerability to flooding, and a significant low‐income population. The research has adopted a mixed methods approach involving different data collection methods governed by the different scales and actors being investigated. The research develops new systems understandings of perceptions and experiences of the local population about adaptation processes in low‐income urban settlements, and how these processes may be positively influenced by integrating bottom‐up and top‐down approaches

Continuation for thin film hydrodynamics and related scalar problems

This chapter illustrates how to apply continuation techniques in the analysis of a particular class of nonlinear kinetic equations that describe the time evolution through transport equations for a single scalar field like a densities or interface profiles of various types. We first systematically introduce these equations as gradient dynamics combining mass-conserving and nonmass-conserving fluxes followed by a discussion of nonvariational amendmends and a brief introduction to their analysis by numerical continuation. The approach is first applied to a number of common examples of variational equations, namely, Allen-Cahn- and Cahn-Hilliard-type equations including certain thin-film equations for partially wetting liquids on homogeneous and heterogeneous substrates as well as Swift-Hohenberg and Phase-Field-Crystal equations. Second we consider nonvariational examples as the Kuramoto-Sivashinsky equation, convective Allen-Cahn and Cahn-Hilliard equations and thin-film equations describing stationary sliding drops and a transversal front instability in a dip-coating. Through the different examples we illustrate how to employ the numerical tools provided by the packages auto07p and pde2path to determine steady, stationary and time-periodic solutions in one and two dimensions and the resulting bifurcation diagrams. The incorporation of boundary conditions and integral side conditions is also discussed as well as problem-specific implementation issues

Urban informality as a site of critical analysis

Across the Global South, the realities of urban informality are changing, with implications for how we understand this phenomenon across economic, spatial, and political domains. Recent accounts have attempted to recognise the diversity of informality across contexts and dimensions, as well as its everyday lived realities. Reviewing key debates in the sector, and drawing upon the new empirical studies in the papers presented here, we argue for a shift away from seeing urban informality narrowly as a setting, sector, or outcome. We suggest that reconsidering informality as a site of critical analysis offers a new perspective that draws on and extends political economy approaches, and helps us to understand processes of stratification and disadvantage. We seek to highlight the significance of the informal-formal continuum at the same time as challenging this dichotomy, and to explore emerging theoretical and empirical developments, including changing attitudes to informality; the increasing salience of agency; and informality as strategy both for elite and subaltern groups

Increasing the power of the poor? NGO-led social accountability initiatives and political capabilities in rural Uganda

Social accountability has become an important new buzzword among development actors seeking to understand the forms of state-society synergy that may be supportive of better public services. Advocates suggest demand-side initiatives are key to increasing the power of the poor in service provision, while sceptics question the application of technical fixes to complex political challenges. This article reports findings from qualitative research into the political capabilities outcomes achieved among local health and education stakeholders through the social accountability interventions of a non-governmental organisation (NGO) in Western Uganda. It argues that NGOs are unlikely to generate substantive advances for social accountability in agrarian contexts characterised by patronage politics without organising marginalised groups themselves to tackle the causes of their disadvantage

A bioassay of some stereoisomeric constituents of allethrin

Volume: 42Start Page: 313End Page: 31