Abstract. Increasing global demand of vegetable oils and biofuels results in significant oil palm expansion in southeastern Asia, predominately in Malaysia and Indonesia. The land conversion to oil palm plantations has posed risks to deforestation (50 % of the oil palm was taken from forest during 1990–2005; Koh and Wilcove, 2008), loss of biodiversity and greenhouse gas emission over the past decades. Quantifying the consequences of oil palm expansion requires fine-scale and frequently updated datasets of land cover dynamics. Previous studies focused on total changes for a multi-year interval without identifying the exact time of conversion, causing uncertainty in the timing of carbon emission estimates from land cover change. Using Advanced Land Observing Satellite (ALOS) Phased Array type L-band Synthetic Aperture Radar (PALSAR), ALOS-2 PALSAR-2 and Moderate Resolution Imaging Spectroradiometer (MODIS) datasets, we produced an annual oil palm area dataset (AOPD) at 100 m resolution in Malaysia and Indonesia from 2001 to 2016. We first mapped the oil palm extent using PALSAR and PALSAR-2 data for 2007–2010 and 2015–2016 and then applied a disturbance and recovery algorithm (Breaks For Additive Season and Trend – BFAST) to detect land cover change time points using MODIS data during the years without PALSAR data (2011–2014 and 2001–2006). The new oil palm land cover maps are assessed to have an accuracy of 86.61 % in the mapping step (2007–2010 and 2015–2016). During the intervening years when MODIS data are used, 75.74 % of the detected change time matched the timing of actual conversion using Google Earth and Landsat images. The AOPD revealed spatiotemporal oil palm dynamics every year and shows that plantations expanded from 2.59 to 6.39×106 ha and from 3.00 to 12.66×106 ha in Malaysia and Indonesia, respectively (i.e. a net increase of 146.60 % and 322.46 %) between 2001 and 2016. The higher trends from our dataset are consistent with those from the national inventories, with limited annual average difference in Malaysia (0.2×106 ha) and Indonesia (−0.17×106 ha). We highlight the capability of combining multiple-resolution radar and optical satellite datasets in annual plantation mapping to a large extent by using image classification and statistical boundary-based change detection to achieve long time series. The consistent characterization of oil palm dynamics can be further used in downstream applications. The annual oil palm plantation maps from 2001 to 2016 at 100 m resolution are published in the Tagged Image File Format with georeferencing information (GeoTIFF) at https://doi.org/10.5281/zenodo.3467071 (Xu et al., 2019).

We present the results of an extensive 3D Brownian dynamics simulation of the self-assembly of colloidal particles for a short-range attractive model that is quenched below its metastable critical point. In particular, results are obtained in the small-volume-fraction, low-temperature region in which we find so-called sticky beads that diffuse around the system, without reaching a final large cluster on the timescale of our simulation. For larger volume fractions in this low-temperature regime, a gel forms as the result of kinetically slowed down spinodal decomposition, as shown earlier for other short-range attractive models (Foffi, G.; De Michele, C.; Sciortino, F.; Tartaglia, P. Phys. Rev. Lett. 2005, 94, 078301. Zaccarelli, E. J. Phys.: Condens. Matter 2007, 19, 323101). We also show that for quenches below the critical point but above the intersection of the binodal with the glass line, two-step crystallization takes place. For sufficiently small volume fractions, the first step is the nucleation of dense fluid drops, followed by the second step of crystallization within these drops, as first proposed for a model of protein crystallization for quenches just above the metastable critical point (ten Wolde, P. R.; Frenkel, D. Science 1997, 277, 1975). For larger values of the volume fraction, the initial step is spinodal decomposition that leads to the formation of an interconnected network of low- and high-density fluids. The second step is crystallization that takes place within the dense fluid phase.

The rheology of near-and off-critical elastomeric blends of polybutadiene (PB)/ low vinyl content polyisoprene (LPI) has been studied as a function of temperature, heating rate, and shear frequency. Depending on the composition, near or far away from the critical point, blends showed different behaviors in several aspects: temperature ramp curves, shift of the apparent binodal and spinodal points under oscillatory shear at the given frequency and strain amplitude. The composition dependent rheological responses are interpreted by the differences in the amplitude of the critical fluctuation near the phase boundary and in the shear induced mixing mechanisms between near-and off-critical blends. For near-critical blends, the critical fluctuation is large enough to induce a considerable extra stress when the blend is still in the miscible state. As a result, a heating rate independent upturn of G′ can be observed and the apparent spinodal point can be greatly shifted through the strong suppression of the large critical fluctuations. In contrast, for off-critical blends, the critical fluctuations in the metastable region are relatively small and there is competition between the phase separation kinetics and the heating rate. Therefore, the blend displayed a heating rate dependent apparent binodal point and a large shift of the apparent binodal point but a moderate shift of the spinodal point under oscillatory shear. By lowering or extrapolating the measured frequency to a very small value (0.1 rad/s in this study) for both binodal and spinodal points, the rheologically determined phase diagram is consistent with the static results obtained by optical microscopy observations.

Event extraction is useful for many practical applications, such as news summarization and information retrieval. However, the popular automatic context extraction (ACE) event extraction program only defines very limited and coarse event schemas, which may not be suitable for practical applications. FrameNet is a linguistic corpus that defines complete semantic frames and frame-to-frame relations. As frames in FrameNet share highly similar structures with event schemas in ACE and many frames actually express events, we propose to redefine the event schemas based on FrameNet. Specifically, we extract frames expressing event information from FrameNet and leverage the frame-to-frame relations to build a hierarchy of event schemas that are more fine-grained and have much wider coverage than ACE. Based on the new event schemas, we propose a joint event extraction approach that leverages the hierarchical structure of event schemas and frame-to-frame relations in FrameNet. The extensive experiments have verified the advantages of our hierarchical event schemas and the effectiveness of our event extraction model. We further apply the results of our event extraction model on news summarization. The results show that the summarization approach based on our event extraction model achieves significant better performance than several state-ofthe-art summarization approaches, which also demonstrates that the hierarchical event schemas and event extraction model are promising to be used in the practical applications.