No abstract

Contextual features always play an important role in Chinese word segmentation (CWS). Wordhood information, being one of the contextual features, is proved to be useful in many conventional character-based segmenters. However, this feature receives less attention in recent neural models and it is also challenging to design a framework that can properly integrate wordhood information from different wordhood measures to existing neural frameworks. In this paper, we therefore propose a neural framework, WMSEG, which uses memory networks to incorporate wordhood information with several popular encoder-decoder combinations for CWS. Experimental results on five benchmark datasets indicate the memory mechanism successfully models wordhood information for neural segmenters and helps WMSEG achieve state-ofthe-art performance on all those datasets. Further experiments and analyses also demonstrate the robustness of our proposed framework with respect to different wordhood measures and the efficiency of wordhood information in cross-domain experiments. 1 * Partially done as an intern at Sinovation Ventures.

We have proposed a five‐layer‐scheme to investigate the volume transport through the South China Sea (SCS) based on the updated Simple Ocean Data Assimilation (SODA2.2.4) product. By demonstrating horizontal transport in each layer, we have revealed different formation mechanisms for the meridional overturning circulation (MOC) in winter and summer in the SCS. Our analysis suggests three meridional circulation systems in the SCS: (1) the seasonal monsoon‐driven circulation in the surface layer, i.e., southward circulation in winter and northward in summer, (2) the compensatory transport‐induced seasonal intermediate MOC in the central SCS, and (3) the persistent deep MOC in the southern SCS all year round. By examining vertical velocity distribution, we have identified that the major overturning process of the intermediate MOC is located along the continental slope east and southeast of Vietnam, while the major overturning process of the deep MOC is located along the continental slope northwest of Borneo. The downwelling in the intermediate MOC in winter and upwelling in the deep MOC all year round bring different water masses to the intermediate and subintermediate layers to be mixed in the SCS. We found no evidence to suggest that the strength and extent of the MOC south of 18°N are related to inter‐ocean volume transport. The surface layer transport in the Luzon Strait has been decreasing since the 1960s. However, the causes of the meridionally staggered and interdecadal alternating acceleration/slowdown of the meridional stream function difference are unknown.

Two high-resolution (4 km) regional climate simulations over a 10-yr period are conducted to study the changes in wintertime precipitation distribution across mountain ranges in the interior western United States (IWUS) in a warming climate. One simulation represents the current climate, and another represents an ~2050 climate using a pseudo–global warming approach. The climate perturbations are derived from the ensemble mean of 15 global climate models from phase 5 of the Coupled Model Intercomparison Project (CMIP5). These simulations provide an estimate of average changes in wintertime orographic precipitation enhancement and finescale distribution across mountain ranges. The variability in these changes among CMIP5 models is quantified using statistical downscaling relations between orographic precipitation distribution and upstream conditions, developed in Part I. The CMIP5 guidance indicates a robust warming signal (~2 K) over the IWUS by ~2050 but minor changes in relative humidity and cloud-base height. The IWUS simulations reveal a widespread increase in precipitation on account of higher precipitation rates during winter storms in this warmer climate. This precipitation increase is most significant over the mountains rather than on the surrounding plains. The increase in precipitation rate is largely due to an increase in low-level cross-mountain moisture transport. The application of the statistical relations indicates that individual CMIP5 models disagree about the magnitude and distribution of orographic precipitation change in the IWUS, although most agree with the ensemble-mean-predicted orographic precipitation increase.

Materials with zero-linear compression (ZLC) and zero-area compression (ZAC) have great promise for specific applications retaining constant in specific directions or planes under external impaction. To date, no more than ten ZLC/ZAC materials have been reported, most of which have very limited working pressure ranges (< 10 GPa). Herein, we report the observation of ZLC and ZAC in Li 2 Ti(IO 3 ) 6 with a gear-spring type structure over an ultra-wide pressure range (0~40 GPa). Structural analysis from the experiment and theoretical calculation reveals that the rotatable metal coordination polyhedra (gears) and extremely compressible metal chains (springs) work together to form an exquisite mechanical unloading device with intrinsic ZLC and ZAC behavior. Moreover, Li 2 Ti(IO 3 ) 6 sets a record-wide ZLC/ZAC working pressure range (up to 40 GPa) among anisotropic compression materials. The demonstration of intrinsic and long-lasting ZLC/ZAC with a gear-spring mechanism allows shock-resistant precision optics to be applied under extreme conditions.