Abstract:We present a simulation and multi-objective optimization framework for the integration of renewable generators and storage devices into an electrical distribution network. The framework searches for the optimal size and location of the distributed renewable generation units (DG). Uncertainties in renewable resources availability, components failure and repair events, loads and grid power supply are incorporated. A Monte Carlo simulation -optimal power flow (MCS-OPF) computational model is used to generate scenarios of the uncertain variables and evaluate the network electric performance. As a response to the need of monitoring and controlling the risk associated to the performance of the optimal DG-integrated network, we introduce the conditional valueat-risk (CVaR) measure into the framework. Multi-objective optimization (MOO) is done with respect to the minimization of the expectations of the global cost (C g ) and energy not supplied (ENS) combined with their respective CVaR values. The multi-objective optimization is performed by the fast non-dominated sorting genetic algorithm NSGA-II. For exemplification, the framework is applied to a distribution network derived from the IEEE 13 nodes test feeder. The results show that the MOO MCS-OPF framework is effective in finding an optimal DG-integrated network considering multiple sources of uncertainties. In addition, from the perspective of decision making, introducing the CVaR as a measure of risk enables the evaluation of trade-offs between optimal expected performances and risks.

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Conflict aggravates disaster risk and impact through increased vulnerability and weakened response capacities. Disaster risk reduction (DRR) and disaster governance are neededbut often deemed unfeasiblein conflict-affected areas. In Afghanistan, despite the high-intensity conflict (HIC), there is a growing body of practice on DRR. To provide insight on DRR in HIC contexts, this study used document analysis, stakeholder interviews, and participant observation to analyse the promotion, implementation, and challenges of DRR in Afghanistan. The findings show that DRR was promoted after international recognition of Afghanistan's high disaster risk, which coincided with expanding opportunities for development. Early Afghan DRR projects were hazard-oriented and focused on mitigation infrastructure, but some have shifted towards an integrated approach. DRR is challenging in HIC contexts because of complex logistical and funding needs required to overcome access and security issues. The Afghan experience shows that DRR is possible in HIC countries, provided that different levels of conflict are acknowledged, sufficient time and funding are available, and disaster governance arrangements are in place. Expectations regarding the possibilities for DRR in HIC areas should be tempered by the realities of limitations in terms of geographical coverage, real impact, and capacities to reduce vulnerability in an integrated way.

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The Covid‐19 pandemic has magnified existing crises and vulnerabilities, but much remains unknown about how it has affected fragile and conflict‐affected settings. This paper builds on the theory that hazards become a disaster in interaction with vulnerability and response policies, yet often lead to renewed disaster risk creation. It is based on seven case studies of countries worldwide that experienced social conflict at the advent of the pandemic, covering the period from March–August 2020. The findings show that authorities instrumentalised Covid‐19 to strengthen their control and agendas. Responsibility was assumed for lockdowns, but this was not accompanied by care to mitigate their adverse effects. Social conflict shaped the response, as high levels of mistrust in authorities complicated the implementation of measures, while authorities did not support community‐based coping initiatives. Whether Covid‐19 will trigger or exacerbate conflict and vulnerabilities depends on pre‐existing, country‐specific conditions, and how a government and other actors frame the issue and respond.

Increasingly complex production environments pose new challenges and require the development of new methodological approaches in the search for effective and cost-efficient maintenance planning, taking into account their applicability in real industrial environments. In this context, this article proposes an extension of the integrated framework for opportunistic preventive maintenance (PM) planning, proposed originally in Viveros et al. integrating non-negligible execution times of PM activities and time-window tolerances criterion for the generation of opportunistic grouping schemes. This work offers the implementation of the proposed framework in a practical case within the Chilean mining industry, expanding the analysis on scarce resource availability scenarios for PM tasks to be performed on conveyor belts in the grinding process. The proposed planning optimization model is formulated under the mixed-integer linear programming (MILP) paradigm, and searches minimizing the asset unavailability under several tolerance levels for the case study analyzed. The results show a 35% downtime reduction for a maximum tolerance factor of 10% considering an unconstrained maintenance resource scenario, which confirms the ability of the model to increase asset availability, minimizing system interruptions, improving its cost efficiency, and enhancing productivity levels in the mining industry.

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Discussions on how humanitarian aid and disaster response can better link with development and disaster risk reduction (DRR) have existed for decades. However, the reverse transition, from development to relief, is still poorly understood. Using the case of Yemen, this study analyses whether and how development and DRR activities adapted to the emerging humanitarian crisis when conflict in the country escalated. The study focuses on governance strategies, actors, challenges, and opportunities in the nexus between development, disaster, and humanitarian responses. Semi-structured interviews and focus group discussions with aid and societal actors were conducted remotely and in Jordan. The findings show gaps in knowledge and coordination in the transition from development and DRR to relief, but also reveal spaces and opportunities to advance towards a better integration of action before, during, and after a crisis. This article contributes to the literature on this nexus and critically argues for the need for a more integrated approach to conflicts and disasters.