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Summary: Tropical forest above-ground wood production (AGWP) varies substantially along environmental gradients. Some evidence suggests that AGWP may vary between regions and specifically that Asian forests have particularly high AGWP. However, comparisons across biogeographic regions using standardized methods are lacking, limiting our assessment of pan-tropical variation in AGWP and potential causes. We sampled AGWP in NW Amazon (17 long-term forest plots) and N Borneo (11 plots), both with abundant year-round precipitation. Within each region, forests growing on a broad range of edaphic conditions were sampled using standardized soil and forest measurement techniques. Plot-level AGWP was 49% greater in Borneo than in Amazonia (9.73 ± 0.56 vs. 6.53 ± 0.34 Mg dry mass ha -1 a -1 , respectively; regional mean ± 1 SE). AGWP was positively associated with soil fertility (PCA axes, sum of bases and total P). After controlling for the edaphic environment, AGWP remained significantly higher in Bornean plots. Differences in AGWP were largely attributable to differing height-diameter allometry in the two regions and the abundance of large trees in Borneo. This may be explained, in part, by the greater solar radiation in Borneo compared with NW Amazonia. Trees belonging to the dominant SE Asian family, Dipterocarpaceae, gained woody biomass faster than otherwise equivalent, neighbouring non-dipterocarps, implying that the exceptional production of Bornean forests may be driven by floristic elements. This dominant SE Asian family may partition biomass differently or be more efficient at harvesting resources and in converting them to woody biomass. Synthesis. N Bornean forests have much greater AGWP rates than those in NW Amazon when soil conditions and rainfall are controlled for. Greater resource availability and the highly productive dipterocarps may, in combination, explain why Asian forests produce wood half as fast again as comparable forests in the Amazon. Our results also suggest that taxonomic groups differ in their fundamental ability to capture carbon and that different tropical regions may therefore have different carbon uptake capacities due to biogeographic history. North Bornean forests have much greater AGWP rates than those in north-western Amazon when soil conditions and rainfall are controlled for. Greater resource availability and the highly productive dipterocarps may, in combination, explain why these Asian forests produce wood half as fast again as comparable forests in the Amazon. Our results also suggest that taxonomic groups differ in their fundamental ability to capture carbon and that different tropical regions may therefore have different carbon uptake capacities due to biogeographic history.

Question: How do trees die in high-mortality and low mortality Amazonian forest regions? Why do trees die in different ways? Location: Humid, lowland forests in Amazonian Peru and Venezuela.

Summary 1. Tree mortality is an important process in forest ecology. We explored the extent to which tropical tree death is a predictable outcome of taxon and individual level properties by means of mixedspecies logistic regression, for trees ≥ 10 cm in diameter. We worked in two lowland forest regions with markedly different floristic composition and dynamic regimes ‐ the high wood density, lowmortality northeastern (NE) Amazon (in eastern Venezuela), and the low wood density, highmortality northwestern (NW) Amazon (in northern Peru). 2. Among those genera that are shared between regions there were no detectable regional differences in mortality rates. This suggests that floristic compositional differences are a major driver of the twofold regional contrast in stand-level mortality. 3. In NE forests, mortality risk of individual trees is best predicted by low taxon-level wood density, slow relative growth, and large size, reflecting phylogenetically determined life-history strategy, physiological stress and senescence. 4. In NW forests, trees with low wood density and slow relative growth are also at most risk, but probability of death is independent of tree size, indicating that senescence is unimportant in this region. 5. Synthesis. This study shows that despite fundamental floristic and dynamic differences between the two Amazonian regions, mortality risk can be predicted with mixed-species, individual-based statistical models and that the predictors are remarkably similar, such that tree growth and wood density both play important roles.

This research proposed lot release policies for color filter fabs based on iterative simulation. Heuristic lot release plan was first developed and used as the input of an AutoMod simulation model to generate the expected performance that was used to improve the release plan and then iteratively simulated.

This research proposes an Order Assignment Policy (OAP) to effectively and efficiently assign orders to color filter fabs. The objectives of this research is to minimize order tardiness and minimize the variance of fab utilization by taking into account fabs ' available capacity and orders ' due date, batch size, product type, and process routing. OAP consists of three modules: Order Priority Module (OPM), WIP-Pulling Module (WPM), and Order Release Module (ORM). OPM assigns different priorities to orders according different dispatching rules. WPM pulls WIP from the end of the process route to meet the orders in Master Production Schedule (MPS). If WIP cannot meet the MPS requirement, ORM is executed to select one of the fabs and release lots into this fab. An AutoMod simulation model is developed, and data of real color filter fabs are collected and used to evaluate OAP's performance based on the design of experiments. Preliminary simulation results show that the combination of OPM using Earliest Due Date (EDD) and ORM using Least Fab Utilization (LFU) leads to the least average lateness of orders, while OPM using Largest Batch Size (LBS) and ORM using LFU results in the least variance of fab utilization.