Resilience is a cross-disciplinary concept that is relevant for understanding the sustainability of the social and environmental conditions in which we live. Most research normatively focuses on building or strengthening resilience, despite growing recognition of the importance of breaking the resilience of, and thus transforming, unsustainable social-ecological systems. Undesirable resilience (cf. lock-ins, social-ecological traps), however, is not only less explored in the academic literature, but its understanding is also more fragmented across different disciplines. This disparity can inhibit collaboration among researchers exploring interdependent challenges in sustainability sciences. In this article, we propose that the term lock-in may contribute to a common understanding of undesirable resilience across scientific fields.

Climate change mitigation relies increasingly on clean technologies such as renewable energy. Despite widespread success, further deployment of renewables has been met with resistance from voters and governments in several countries. How resilient is the renewable energy industry to adverse political events? I use the unexpected election of Donald Trump in the 2016 U.S. presidential race to study this question. As a vocal critic of renewables and a supporter of fossil fuels, his election is a plausible negative shock to the renewable energy sector. I examine stock market data to gauge the reaction of investors. I find that renewable energy stocks were adversely affected by the election. Overall, they experienced a cumulative abnormal loss in share values of about 6 percent on average over the twenty days that followed the election. However, I find that the negative effect is concentrated among non-U.S. firms. U.S. firms, on average, emerged unscathed. Non-U.S. companies, on the other hand, lost over 14 percent of their value in the aftermath of the election. This suggests that markets are more concerned by increasing obstacles to international business than a decrease of federal support for renewables.

Vortex-induced vibration (VIV) is an important physical phenomenon as one design a riser or a cylindrical structure in ocean. As the riser or the cylindrical structure is adjacent to a seabed, the boundary effect on VIV is not fully understood yet. The direct-forcing immersed boundary (DFIB) method is used to investigate a two-degree-of-freedom VIV of a flexible supported circular cylinder adjacent to a plane boundary in this study. Furthermore, the effect of the VIV of cylinder on skin friction of the plane boundary is investigated. The effects of varying reduced velocity and gap ratio on VIV are discussed. Only a single vortex street is found when the cylinder is close to plane boundary. Hydrodynamic coefficients of the freely vibrating cylinder are analyzed in time and spectral domains. Furthermore, nearly round oval-shaped motion is observed as the so-called lock-in phenomenon occurs. The skin friction of the plane boundary is predicted by the DFIB model. Results show that the vibrating cylinder in the boundary layer flow can reduce the friction effectively. This proposed DFIB model can be useful for the investigation of VIV of the structures under the plane boundary effect even for a small gap between the cylinder and the boundary.

A new computational procedure is developed to solve the external field problems of the incompressible viscous flows. The method is able to solve the infinite boundary value problems by extracting the boundary effects coming from the finite computational domain. The present method is based on the projection method of the Navier-Stokes equations. We use three-step explicit finite element method to solve the momentum equation of the flow motion. The external field solver of the boundary element is used to treat the pressure Poisson equation. The arbitrary Lagrangian-Eulerian method is employed to deal with the moving boundary, such as wind-structure interaction problems. For illustration of the present numerical code, a vortex-induced cross-flow oscillations of a circular cylinder mounted on an elastic dashpot-spring system is considered. The phenomena of the beat, lock-in, and resonance are revealed in the Reynolds number range between 100 and 110, which are much narrower than the previous studies.