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Different Earth observation resources (EORs) [e.g., satellites, airships, and unmanned aerial vehicles (UAVs)] are usually managed by different organization sub-planners, which lack interactions and cooperation among one another. Such independent resource operations are no longer efficient to meet diverse and vast observation requests, especially in emergency situations, such as earthquakes, flooding, and forest fire disasters. This paper addresses the issue of coordinated planning of heterogeneous EORs, including satellites, airships, and UAVs. A hierarchical coordinated planning architecture is proposed to integrate heterogeneous EORs for the construction of a distributed and loosely coupled Earth observation system. The architecture comprises four component categories, namely, observation resource, sub-planner, coordination, and information management. Moreover, we propose two task assignment algorithms to coordinate and allocate observation tasks to sub-planners. The first algorithm is a highest-weight-first-allocated algorithm, and the second is a tabu-list-based simulated annealing (SA-TL) algorithm. Experiments and comparative studies demonstrate the efficiency of the coordinated planning architecture and SA-TL algorithm. We also show that the system responds dynamically to unexpected situations through effective disturbance-handling mechanisms.

We have studied melting of poly­(butylene succinate), isothermally crystallized over a wide temperature range, employing a combination of the Hoffman–Weeks plot and the Gibbs–Thomson crystallization line, determined by small-angle X-ray scattering measurements. A change in the slope α of the Hoffman–Weeks (H–W) line, accompanied by a change of the slope of the crystallization line, was observed for crystallization temperatures higher than 110 °C. α was reaching a value of 1, implying that no intersection point between the H–W line and the T m = T c line could be obtained. (T m is the measured melting temperature and T c is the temperature at which the sample was crystallized). This observation was corroborated by the crystallization line, which was found to be parallel to the melting line for T c > 110 °C. We relate these changes in slope to different stabilization mechanisms of the secondary nuclei at the growth front of polymer lamellar crystals. For T c > 110 °C, secondary nuclei are proposed to be stabilized by coalescence of neighboring nuclei, all having a small width. By contrast, for T c > 110 °C, the number density of secondary nuclei is low and thus their coalescence is rare. Accordingly, nuclei are stabilized by growing in size, mainly increasing their width.

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e applications of steel slag powder and steel slag aggregate in ultra-high performance concrete (UHPC) were investigated by determining the fluidity, nonevaporable water content, and pore structure of paste and the compressive strength of concrete and by observing the morphologies of hardened paste and the concrete fracture surface. e results show that the fluidity of the paste containing steel slag is higher. e nonevaporable water content of the hardened paste containing steel slag powder is close to that of the control sample at late ages. Both steel slag powder and steel slag aggregate react and connect tightly to gels and hardened paste, respectively. When the cement replacement ratio is no more than 10%, the proportion of pores larger than 50 nm in the hardened paste containing steel slag powder is close to that of the control sample, and the UHPC containing steel slag powder can display satisfactory compressive strengths. e UHPC containing steel slag aggregate demonstrates higher compressive strengths.