Unidirectional solidification of pivalic acid （PVA）-ethanol （Eth） mixture was performed to examine whether an allowable range of primary dendrite spacing definitely exists at a given growth velocity and how the ra...Unidirectional solidification of pivalic acid （PVA）-ethanol （Eth） mixture was performed to examine whether an allowable range of primary dendrite spacing definitely exists at a given growth velocity and how the range is history-dependent. PVA-0.59 wt pct Eth was unidirectionally solidified in the range of growth velocity 0.5-64 μm/s at the temperature gradient of 2.3 K/ram. Sequential change in growth velocity was imposed to determine the upper and lower limits for the allowable range of stable spacing. An allowable range of the steady state primary spacing was observed at a given growth velocity, and the extent of the range seems to be dependent on the degree to which step-increase or step-decrease in growth velocity is accomplished. As the degree of sequential change in growth velocity increases, the history-dependence of the selection for the primary dendrite spacing tends to disappear.展开更多
SINCE 1956, Michael’s continuous selection theory has been applied to functional analysis,topology, approximation theory and other mathematical fields. In this letter, the concept ofthe pseudo-lower semicontinuity is...SINCE 1956, Michael’s continuous selection theory has been applied to functional analysis,topology, approximation theory and other mathematical fields. In this letter, the concept ofthe pseudo-lower semicontinuity is introduced, and a convex structure of metric space is de-fined. A continuous selection theorem for pseudo-lower semicontinuity is given. This展开更多
Photonic integrated switches that are both space and wavelength selective are a highly promising technology for data-intensive applications as they benefit from multi-dimensional manipulation of optical signals.Howeve...Photonic integrated switches that are both space and wavelength selective are a highly promising technology for data-intensive applications as they benefit from multi-dimensional manipulation of optical signals.However,scaling these switches normally poses stringent challenges such as increased fabrication complexity and control difficulties,due to the growing number of switching elements.In this work,we propose a new type of dilated crosspoint topology,which efficiently handles both space and wavelength selective switching,while reducing the required switching element count by an order of magnitude compared to reported designs.To the best of our knowledge,our design requires the fewest switching elements for an equivalent routing paths number and it fully cancels the first-order in-band crosstalk.We demonstrate such an ultra-compact space-and-wavelength selective switch(SWSS)at a scale of 4×4×4λ on the silicon-on-insulator(SOI)platform.Experimental results reveal that the switch achieves an insertion loss ranging from 2.3 dB to 8.6 dB and crosstalk levels in between−35.3 dB and−59.7 dB.The add-drop microring-resonators(MRRs)are equipped with micro-heaters,exhibiting a rise and fall time of 46μs and 0.33μs,respectively.These performance characteristics highlight the switch’s ultralow element count and crosstalk with low insertion loss,making it a promising candidate for advanced data center applications.展开更多
This study explores the potential of the advanced selective state spaces model(SSSM)in modeling complicated process industries system and proposes the process industry state identification model(PISIM)for controlled p...This study explores the potential of the advanced selective state spaces model(SSSM)in modeling complicated process industries system and proposes the process industry state identification model(PISIM)for controlled prediction of flotation cell pulp level.As a neural system identification model,the PISIM inherits two advantages of the SSSM to address the challenges in identifying flotation systems,including modeling the impact of frequent upstream fluctuations on system states,complex nonlinear physicochemical processes,and long-term dependencies.The first advantage is the ability to capture long-range dependencies,thereby boosting its long-term predictive accuracy.The second lies in the model structure adhering to scaling laws,enabling ongoing enhancements in performance as datasets expand.PISIM is evaluated using a real industrial dataset from a flotation plant at a copper mine in Zambia,with the results demonstrating its theoretical advantages.In a 4.5-hour pulp level prediction task,PISIM outperforms the baseline model by more than 31.34%.Furthermore,a flotation process control simulation experimental system based on PISIM is developed and deployed in a flotation plant in Zambia,assisting engineers in evaluating and optimizing setpoint strategies,ensuring stable production and improving production efficiency.展开更多
文摘Unidirectional solidification of pivalic acid （PVA）-ethanol （Eth） mixture was performed to examine whether an allowable range of primary dendrite spacing definitely exists at a given growth velocity and how the range is history-dependent. PVA-0.59 wt pct Eth was unidirectionally solidified in the range of growth velocity 0.5-64 μm/s at the temperature gradient of 2.3 K/ram. Sequential change in growth velocity was imposed to determine the upper and lower limits for the allowable range of stable spacing. An allowable range of the steady state primary spacing was observed at a given growth velocity, and the extent of the range seems to be dependent on the degree to which step-increase or step-decrease in growth velocity is accomplished. As the degree of sequential change in growth velocity increases, the history-dependence of the selection for the primary dendrite spacing tends to disappear.
文摘SINCE 1956, Michael’s continuous selection theory has been applied to functional analysis,topology, approximation theory and other mathematical fields. In this letter, the concept ofthe pseudo-lower semicontinuity is introduced, and a convex structure of metric space is de-fined. A continuous selection theorem for pseudo-lower semicontinuity is given. This
基金Engineering and Physical Sciences Research Council (EP/T028475/1)European Union's Horizon Europe Research and Innovation Program (101070560,101017088)。
文摘Photonic integrated switches that are both space and wavelength selective are a highly promising technology for data-intensive applications as they benefit from multi-dimensional manipulation of optical signals.However,scaling these switches normally poses stringent challenges such as increased fabrication complexity and control difficulties,due to the growing number of switching elements.In this work,we propose a new type of dilated crosspoint topology,which efficiently handles both space and wavelength selective switching,while reducing the required switching element count by an order of magnitude compared to reported designs.To the best of our knowledge,our design requires the fewest switching elements for an equivalent routing paths number and it fully cancels the first-order in-band crosstalk.We demonstrate such an ultra-compact space-and-wavelength selective switch(SWSS)at a scale of 4×4×4λ on the silicon-on-insulator(SOI)platform.Experimental results reveal that the switch achieves an insertion loss ranging from 2.3 dB to 8.6 dB and crosstalk levels in between−35.3 dB and−59.7 dB.The add-drop microring-resonators(MRRs)are equipped with micro-heaters,exhibiting a rise and fall time of 46μs and 0.33μs,respectively.These performance characteristics highlight the switch’s ultralow element count and crosstalk with low insertion loss,making it a promising candidate for advanced data center applications.
基金supported by the National Natural Science Foundation of China(62506031,62332017,U22A2022)National Science and Technology Major Project of the Ministry of Science and Technology of China(2024ZD0608100).
文摘This study explores the potential of the advanced selective state spaces model(SSSM)in modeling complicated process industries system and proposes the process industry state identification model(PISIM)for controlled prediction of flotation cell pulp level.As a neural system identification model,the PISIM inherits two advantages of the SSSM to address the challenges in identifying flotation systems,including modeling the impact of frequent upstream fluctuations on system states,complex nonlinear physicochemical processes,and long-term dependencies.The first advantage is the ability to capture long-range dependencies,thereby boosting its long-term predictive accuracy.The second lies in the model structure adhering to scaling laws,enabling ongoing enhancements in performance as datasets expand.PISIM is evaluated using a real industrial dataset from a flotation plant at a copper mine in Zambia,with the results demonstrating its theoretical advantages.In a 4.5-hour pulp level prediction task,PISIM outperforms the baseline model by more than 31.34%.Furthermore,a flotation process control simulation experimental system based on PISIM is developed and deployed in a flotation plant in Zambia,assisting engineers in evaluating and optimizing setpoint strategies,ensuring stable production and improving production efficiency.
