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This paper aims to establish the relationship between crosswind speed and pantograph-catenary lateral deviation, as well as quantify the influence of crosswind speed and rod size uncertainty on pantograph-catenary contact reliability.

The closed vector method is used to establish the pantograph-catenary kinematics formula. A new prediction model is proposed by using the bird swarm algorithm to optimize the grey model. The lateral deviation of the pantograph and catenary is predicted via the new model. Then the relationship between the effective length of the rod and operating mileage is inferred by combining the effective length theory with the Gamma process, as well as the pantograph-catenary contact reliability model is established according to reliability theory.

The results obtained show the impacts of uncertainty design parameters of pantograph rods on pantograph-catenary contact reliability index, and the results at crosswind speed of 0 ms⁻¹ and 5 ms⁻¹ are 5.0630 and 4.1442, respectively. The reliability decreases with the increasing crosswind speed, and can be greater than the reliability calculated for rod size degradation due to long-term use.

Most preceding works on pantograph-catenary contact reliability were based on principles of dynamics, without considering the pantograph-catenary relative motion. This research reveals the law of pantograph-catenary relative motion for uncertainty design parameters and crosswind, and quantifies the reliability from the angle of kinematics.

To coordinate humanitarian organisations with different mandates that flock the scenes of disasters to save lives and respond to varied needs arising from the increased number of victims is not easy. Therefore, the level at which organisations self-organise, network and adapt to the dynamic operational environment may be related to inter-organisational coordination. The authors studied self-organisation, organisational networks and adaptability as important and often overlooked organisational factors hypothesised to be related to inter-organisational coordination in the context of humanitarian organisations.

The study’s sample consisted of 101 humanitarian organisations with 315 respondents. To decrease the problem of common method variance, the authors split the samples within each humanitarian organisation into two subsamples: one subsample was used for the measurement of self-organisation, organisational network and adaptability, while the other was for the measurement of inter-organisational coordination.

The partial least square structural equation modelling (PLS-SEM) analysis using SmartPLS 3.2.8 indicated that self-organisation is related to inter-organisational coordination. Organisational network and adaptability were found to be mediators for the relationship between self-organisation and inter-organisational coordination and all combined accounted for 57.8% variance in inter-organisational coordination.

The study was cross sectional, hence imposing a limitation on changes in perceptions over time. Perhaps, a longitudinal study in future is desirable. Data were collected only from humanitarian organisations that had delivered relief to refugees in the stated camps by 2018. Above all, this study considered self-organisation, adaptability and organisational networks in the explanation of inter-organisational coordination, although there are other factors that could still be explored.

A potential implication is that humanitarian organisations which need to coordinate with others in emergency situations may need to examine their ability to self-organise, network and adapt.

Social transformation is a function of active social entities that cannot work in isolation. Hence, for each to be able to make a contribution to meaningful social change, there is need to develop organisational networks with sister organisations so as to secure rare resources that facilitate change efforts coupled with the ability to reorganise themselves and adapt to changing environmental circumstances.

The paper examines (1) the extent to which self-organisation, adaptability and organisational networks influence inter-organisational coordination; (2) the mediating role of both adaptability and organisational networks between self-organisation and inter-organisational coordination in the context of humanitarian organisations against the backdrop of complex adaptive system (CAS) theory.