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NADARAYA-WATSON ESTIMATORS FOR REFLECTED STOCHASTIC PROCESSES
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作者 韩月才 张丁文 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期143-160,共18页
We study the Nadaraya-Watson estimators for the drift function of two-sided reflected stochastic differential equations.The estimates,based on either the continuously observed process or the discretely observed proces... We study the Nadaraya-Watson estimators for the drift function of two-sided reflected stochastic differential equations.The estimates,based on either the continuously observed process or the discretely observed process,are considered.Under certain conditions,we prove the strong consistency and the asymptotic normality of the two estimators.Our method is also suitable for one-sided reflected stochastic differential equations.Simulation results demonstrate that the performance of our estimator is superior to that of the estimator proposed by Cholaquidis et al.(Stat Sin,2021,31:29-51).Several real data sets of the currency exchange rate are used to illustrate our proposed methodology. 展开更多
关键词 reflected stochastic differential equation discretely observed process continuously observed process Nadaraya-Watson estimator asymptotic behavior
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Multimodal Data-Driven Reinforcement Learning for Operational Decision-Making in Industrial Processes
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作者 Chenliang Liu Yalin Wang +1 位作者 Chunhua Yang Weihua Gui 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期252-254,共3页
Dear Editor, This letter proposes a multimodal data-driven reinforcement learning-based method for operational decision-making in industrial processes. Due to the frequent fluctuations of feedstock properties and oper... Dear Editor, This letter proposes a multimodal data-driven reinforcement learning-based method for operational decision-making in industrial processes. Due to the frequent fluctuations of feedstock properties and operating conditions in the industrial processes, existing data-driven methods cannot effectively adjust the operational variables. In addition, multimodal data such as images, audio. 展开更多
关键词 processes MODAL ADJUST
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Correlation of Microbiological Stability with Redox Processes in White Wines
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作者 Gheorghe Duca Rodica Sturza +1 位作者 Natalia Vladei Ecaterina Covaci 《Food and Nutrition Sciences》 CAS 2024年第3期211-223,共13页
In this paper, the authors analyzed the correlation between the microbiological stability of white wines and the content of sulfur dioxide, which influences the main redox processes that take place in the technologica... In this paper, the authors analyzed the correlation between the microbiological stability of white wines and the content of sulfur dioxide, which influences the main redox processes that take place in the technological stages of the wine. The consecutive, parallel and spontaneous development of several redox processes and their impact on the quality, microbiological and crystalline stability of white wines were examined. The reduction of additive and subtractive technological interventions, of the amounts of adjuvants (sulphurous anhydride) is essential for the production of organic wines. 展开更多
关键词 White Wines ACETOBACTER Sulfur Dioxide Redox processes OXYGEN
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THE EXTREMES OF DEPENDENT CHI-PROCESSES ATTRACTED BY THE BROWN-RESNICK PROCESS
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作者 孙俊杰 谭中权 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期686-701,共16页
Motivated by some recent works on the topic of the Brown-Resnick process, we study the functional limit theorem for normalized pointwise maxima of dependent chi-processes. It is proven that the properly normalized poi... Motivated by some recent works on the topic of the Brown-Resnick process, we study the functional limit theorem for normalized pointwise maxima of dependent chi-processes. It is proven that the properly normalized pointwise maxima of those processes are attracted by the Brown-Resnick process. 展开更多
关键词 chi-processes Brown-Resnick process pointwise maxima functional limit theorem
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Modeling and analysis of air combustion and steam regeneration in methanol to olefins processes
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作者 Jinqiang Liang Danzhu Liu +1 位作者 Shuliang Xu Mao Ye 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期94-103,共10页
Light olefins is the incredibly important materials in chemical industry.Methanol to olefins(MTO),which provides a non-oil route for light olefins production,received considerable attention in the past decades.However... Light olefins is the incredibly important materials in chemical industry.Methanol to olefins(MTO),which provides a non-oil route for light olefins production,received considerable attention in the past decades.However,the catalyst deactivation is an inevitable feature in MTO processes,and regeneration,therefore,is one of the key steps in industrial MTO processes.Traditionally the MTO catalyst is regenerated by removing the deposited coke via air combustion,which unavoidably transforms coke into carbon dioxide and reduces the carbon utilization efficiency.Recent study shows that the coke species over MTO catalyst can be regenerated via steam,which can promote the light olefins yield as the deactivated coke species can be essentially transferred to industrially useful synthesis gas,is a promising pathway for further MTO processes development.In this work,we modelled and analyzed these two MTO regeneration methods in terms of carbon utilization efficiency and technology economics.As shown,the steam regeneration could achieve a carbon utilization efficiency of 84.31%,compared to 74.74%for air combustion regeneration.The MTO processes using steam regeneration can essentially achieve the near-zero carbon emission.In addition,light olefins production of the MTO processes using steam regeneration is 12.81%higher than that using air combustion regeneration.In this regard,steam regeneration could be considered as a potential yet promising regeneration method for further MTO processes,showing not only great environmental benefits but also competitive economic performance. 展开更多
关键词 Model Methanol to olefins REGENERATION Greenhouse gas processes simulation
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Multi-Perspective Data Fusion Framework Based on Hierarchical BERT: Provide Visual Predictions of Business Processes
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作者 Yongwang Yuan Xiangwei Liu Ke Lu 《Computers, Materials & Continua》 SCIE EI 2024年第1期1227-1252,共26页
Predictive Business Process Monitoring(PBPM)is a significant research area in Business Process Management(BPM)aimed at accurately forecasting future behavioral events.At present,deep learning methods are widely cited ... Predictive Business Process Monitoring(PBPM)is a significant research area in Business Process Management(BPM)aimed at accurately forecasting future behavioral events.At present,deep learning methods are widely cited in PBPM research,but no method has been effective in fusing data information into the control flow for multi-perspective process prediction.Therefore,this paper proposes a process prediction method based on the hierarchical BERT and multi-perspective data fusion.Firstly,the first layer BERT network learns the correlations between different category attribute data.Then,the attribute data is integrated into a weighted event-level feature vector and input into the second layer BERT network to learn the impact and priority relationship of each event on future predicted events.Next,the multi-head attention mechanism within the framework is visualized for analysis,helping to understand the decision-making logic of the framework and providing visual predictions.Finally,experimental results show that the predictive accuracy of the framework surpasses the current state-of-the-art research methods and significantly enhances the predictive performance of BPM. 展开更多
关键词 Business process prediction monitoring deep learning attention mechanism BERT multi-perspective
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Comparison of a Spectral Bin and Two Multi-Moment Bulk Microphysics Schemes for Supercell Simulation:Investigation into Key Processes Responsible for Hydrometeor Distributions and Precipitation
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作者 Marcus JOHNSON Ming XUE Youngsun JUNG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期784-800,共17页
There are more uncertainties with ice hydrometeor representations and related processes than liquid hydrometeors within microphysics parameterization(MP)schemes because of their complicated geometries and physical pro... There are more uncertainties with ice hydrometeor representations and related processes than liquid hydrometeors within microphysics parameterization(MP)schemes because of their complicated geometries and physical properties.Idealized supercell simulations are produced using the WRF model coupled with“full”Hebrew University spectral bin MP(HU-SBM),and NSSL and Thompson bulk MP(BMP)schemes.HU-SBM downdrafts are typically weaker than those of the NSSL and Thompson simulations,accompanied by less rain evaporation.HU-SBM produces more cloud ice(plates),graupel,and hail than the BMPs,yet precipitates less at the surface.The limiting mass bins(and subsequently,particle size)of rimed ice in HU-SBM and slower rimed ice fall speeds lead to smaller melting-level net rimed ice fluxes than those of the BMPs.Aggregation from plates in HU-SBM,together with snow–graupel collisions,leads to a greater snow contribution to rain than those of the BMPs.Replacing HU-SBM’s fall speeds using the formulations of the BMPs after aggregating the discrete bin values to mass mixing ratios and total number concentrations increases net rain and rimed ice fluxes.Still,they are smaller in magnitude than bulk rain,NSSL hail,and Thompson graupel net fluxes near the surface.Conversely,the melting-layer net rimed ice fluxes are reduced when the fall speeds for the NSSL and Thompson simulations are calculated using HU-SBM fall speed formulations after discretizing the bulk particle size distributions(PSDs)into spectral bins.The results highlight precipitation sensitivity to storm dynamics,fall speed,hydrometeor evolution governed by process rates,and MP PSD design. 展开更多
关键词 PRECIPITATION spectral bin microphysics bulk microphysics parameterization microphysics processes WRF model supercell storm
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Local Torrential Rainfall Event within a Mei-Yu Season Mesoscale Convective System:Importance of Back-Building Processes
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作者 Honglei ZHANG Ming XUE +2 位作者 Hangfeng SHEN Xiaofan LI Guoqing ZHAI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期847-863,共17页
An extreme rainfall event occurred over Hangzhou,China,during the afternoon hours on 24 June 2013.This event occurred under suitable synoptic conditions and the maximum 4-h cumulative rainfall amount was over 150 mm.T... An extreme rainfall event occurred over Hangzhou,China,during the afternoon hours on 24 June 2013.This event occurred under suitable synoptic conditions and the maximum 4-h cumulative rainfall amount was over 150 mm.This rainfall event had two major rainbands.One was caused by a quasi-stationary convective line,and the other by a backbuilding convective line related to the interaction of the outflow boundary from the first rainband and an existing low-level mesoscale convergence line associated with a mei-yu frontal system.The rainfall event lasted 4 h,while the back-building process occurred in 2 h when the extreme rainfall center formed.So far,few studies have examined the back-building processes in the mei-yu season that are caused by the interaction of a mesoscale convergence line and a convective cold pool.The two rainbands are successfully reproduced by the Weather Research and Forecasting(WRF)model with fourlevel,two-way interactive nesting.In the model,new cells repeatedly occur at the west side of older cells,and the backbuilding process occurs in an environment with large CAPE,a low LFC,and plenty of water vapor.Outflows from older cells enhance the low-level convergence that forces new cells.High precipitation efficiency of the back-building training cells leads to accumulated precipitation of over 150 mm.Sensitivity experiments without evaporation of rainwater show that the convective cold pool plays an important role in the organization of the back-building process in the current extreme precipitation case. 展开更多
关键词 torrential rainfall back-building processes numerical simulation trigger mechanism convergence line convective cold pool
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Solid-state impedance spectroscopy studies of dielectric properties and relaxation processes in Na_(2)O–V_(2)O_(5)–Nb_(2)O_(5)–P_(2)O_(5) glass
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作者 Sara Marijan Luka Pavic 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期186-196,共11页
Solid-state impedance spectroscopy(SS-IS)was used to investigate the influence of structural modifications resulting from the addition of Nb2O5 on the dielectric properties and relaxation processes in the quaternary m... Solid-state impedance spectroscopy(SS-IS)was used to investigate the influence of structural modifications resulting from the addition of Nb2O5 on the dielectric properties and relaxation processes in the quaternary mixed glass former(MGF)system 35Na_(2)O–10V_(2)O_(5)–(55-x)P_(2)O_(5)–xNb_(2)O_(5)(x=0–40,mol%).The dielectric parameters,including the dielectric strength and dielectric loss,are determined from the frequency and temperature-dependent complex permittivity data,revealing a significant dependence on the Nb2O5 content.The transition from a predominantly phosphate glass network(x<10,region I)to a mixed niobate–phosphate glass net-work(10≤x≤20,region II)leads to an increase in the dielectric parameters,which correlates with the observed trend in the direct-cur-rent(DC)conductivity.In the predominantly niobate network(x≥25,region III),the highly polarizable nature of Nb5+ions leads to a fur-ther increase in the dielectric permittivity and dielectric strength.This is particularly evident in Nb-40 glass-ceramic,which contains Na_(13)Nb_(35)O_(94) crystalline phase with a tungsten bronze structure and exhibits the highest dielectric permittivity of 61.81 and the lowest loss factor of 0.032 at 303 K and 10 kHz.The relaxation studies,analyzed through modulus formalism and complex impedance data,show that DC conductivity and relaxation processes are governed by the same mechanism,attributed to ionic conductivity.In contrast to glasses with a single peak in frequency dependence of imaginary part of electrical modulus,M″(ω),Nb-40 glass-ceramic exhibits two distinct contributions with similar relaxation times.The high-frequency peak indicates bulk ionic conductivity,while the additional low-fre-quency peak is associated with the grain boundary effect,confirmed by the electrical equivalent circuit(EEC)modelling.The scaling characteristics of permittivity and conductivity spectra,along with the electrical modulus,validate time-temperature superposition and demonstrate a strong correlation with composition and modification of the glass structure upon Nb_(2)O_(5) incorporation. 展开更多
关键词 phosphate glasses GLASS-CERAMICS impedance spectroscopy dielectric properties relaxation processes permittivity scaling conductivity scaling modulus formalism
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Metallogenic Processes:Evidencesfrom Zoning Patterns of Mineralization and alteration and fluid inclusion geochemistryin the Lehong Zn-Pb Deposit in Northeastern Yunnan, China
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作者 ZHAO dong HAN Runshen +4 位作者 REN Tao WANG Jiasheng ZHANG Xiao-pei WU Yongtao CUI Junhao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期251-252,共2页
1 Introduction The large clusters of Zn-Pb deposits in northeastern Yunnan,located in the southwestern margin of the Yangtze Block,are an important part of the Sichuan-YunnanGuizhou Pb-Zn Poly-metallic Metallogenic Tr... 1 Introduction The large clusters of Zn-Pb deposits in northeastern Yunnan,located in the southwestern margin of the Yangtze Block,are an important part of the Sichuan-YunnanGuizhou Pb-Zn Poly-metallic Metallogenic Triangle 展开更多
关键词 In Pb Metallogenic processes:evidencesfrom Zoning Patterns of Mineralization and alteration and fluid inclusion geochemistryin the Lehong Zn-Pb Deposit in Northeastern Yunnan China Zn
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On the Key Dynamical Processes Supporting the 21.7 Zhengzhou Record-breaking Hourly Rainfall in China 被引量:10
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作者 Peng WEI Xin XU +6 位作者 Ming XUE Chenyue ZHANG Yuan WANG Kun ZHAO Ang ZHOU Shushi ZHANG Kefeng ZHU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第3期337-349,共13页
An extremely heavy rainfall event occurred in Zhengzhou,China,on 20 July 2021 and produced an hourly rainfall rate of 201.9 mm,which broke the station record for China's Mainland.Based on radar observations and a ... An extremely heavy rainfall event occurred in Zhengzhou,China,on 20 July 2021 and produced an hourly rainfall rate of 201.9 mm,which broke the station record for China's Mainland.Based on radar observations and a convection-permitting simulation using the WRF-ARW model,this paper investigates the multiscale processes,especially those at the mesoscale,that support the extreme observed hourly rainfall.Results show that the extreme rainfall occurred in an environment characteristic of warm-sector heavy rainfall,with abundant warm moist air transported from the ocean by an abnormally northward-displaced western Pacific subtropical high and Typhoon In-Fa(2021).However,rather than through back building and echo training of convective cells often found in warm-sector heavy rainfall events,this extreme hourly rainfall event was caused by a single,quasi-stationary storm in Zhengzhou.Scale separation analysis reveals that the extreme-rainproducing storm was supported and maintained by the dynamic lifting of low-level converging flows from the north,south,and east of the storm.The low-level northerly flow originated from a mesoscale barrier jet on the eastern slope of the Taihang Mountain due to terrain blocking of large-scale easterly flows,which reached an overall balance with the southerly winds in association with a low-level meso-β-scale vortex located to the west of Zhengzhou.The large-scale easterly inflows that fed the deep convection via transport of thermodynamically unstable air into the storm prevented the eastward propagation of the weak,shallow cold pool.As a result,the convective storm was nearly stationary over Zhengzhou,resulting in record-breaking hourly precipitation. 展开更多
关键词 extreme rainfall multiscale processes OROGRAPHY barrier jet low-level mesoscale vortex
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Effect of cooking processes on tilapia aroma and potential umami perception 被引量:1
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作者 Danni Zhang Charfedinne Ayed +1 位作者 Ian D.Fisk Yuan Liu 《Food Science and Human Wellness》 SCIE CSCD 2023年第1期35-44,共10页
Tilapia is a freshwater fish group with a sustainable prospect but suffers off-notes appearing during cooking processes.To promote pleasant odorants by thermal cooking processes,tilapia fillets were cooked in differen... Tilapia is a freshwater fish group with a sustainable prospect but suffers off-notes appearing during cooking processes.To promote pleasant odorants by thermal cooking processes,tilapia fillets were cooked in different ways(roasting,microwave-heating,boiling and steaming).Their aroma profiles were analysed with special focus on off-notes and umami-enhancing odorants by principal component analysis,and correlated with the heating time,colour,moisture and water activity by partial least squares regression analysis.Results showed that the“green”and“earthy”off-notes were highly correlated with the boiling process(excess of water,short heating time),while most of the umami-enhancing odorants had a high association with the roasting process(low water content,long heating time,better Maillard reaction).This study indicated that roasting is the most adapted cooking process promoting Maillard-derived aromas,umami-enhancing aromas and meanwhile,reducing off-notes.This research helps in understanding the off-note generation in tilapia and promoting desirable umami-enhancing odorants. 展开更多
关键词 TILAPIA Thermal cooking process AROMA Off-note UMAMI
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Finite Element Simulation of Radial Tire Building and Shaping Processes Using an Elasto-Viscoplastic Model 被引量:1
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作者 Yinlong Wang Zhao Li +1 位作者 Ziran Li Yang Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第5期1187-1208,共22页
The comprehensive tire building and shaping processes are investigated through the finite element method(FEM)in this article.The mechanical properties of the uncured rubber from different tire components are investiga... The comprehensive tire building and shaping processes are investigated through the finite element method(FEM)in this article.The mechanical properties of the uncured rubber from different tire components are investigated through cyclic loading-unloading experiments under different strain rates.Based on the experiments,an elastoviscoplastic constitutive model is adopted to describe themechanical behaviors of the uncured rubber.The distinct mechanical properties,including the stress level,hysteresis and residual strain,of the uncured rubber can all be well characterized.The whole tire building process(including component winding,rubber bladder inflation,component stitching and carcass band folding-back)and the shaping process are simulated using this constitutive model.The simulated green tire profile is in good agreement with the actual profile obtained through 3D scanning.The deformation and stress of the rubber components and the cord reinforcements during production can be obtained fromthe FE simulation,which is helpful for judging the rationality of the tire construction design.Finally,the influence of the parameter“drum width”is investigated,and the simulated result is found to be consistent with the experimental observations,which verifies the effectiveness of the simulation.The established simulation strategy provides some guiding significance for the improvement of tire design parameters and the elimination of tire production defects. 展开更多
关键词 Uncured rubber constitutive modeling radial tire building process finite element method
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Microfluidic field strategy for enhancement and scale up of liquid-liquid homogeneous chemical processes by optimization of 3D spiral baffle structure 被引量:1
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作者 Shuangfei Zhao Yingying Nie +7 位作者 Wenyan Zhang Runze Hu Lianzhu Sheng Wei He Ning Zhu Yuguang Li Dong Ji Kai Guo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第4期255-265,共11页
Due to the scale effect, the uniform distribution of reagents in continuous flow reactor becomes bad when the channel is enlarged to tens of millimeters. Microfluidic field strategy was proposed to produce high mixing... Due to the scale effect, the uniform distribution of reagents in continuous flow reactor becomes bad when the channel is enlarged to tens of millimeters. Microfluidic field strategy was proposed to produce high mixing efficiency in large-scale channel. A 3D spiral baffle structure(3SBS) was designed and optimized to form microfluidic field disturbed by continuous secondary flow in millimeter scale Y-shaped tube mixer(YSTM). Enhancement effect of the 3SBS in liquid-liquid homogeneous chemical processes was verified and evaluated through the combination of simulation and experiment. Compared with 1 mm YSTM, 10 mm YSTM with 3SBS increased the treatment capacity by 100 times, shortened the basic complete mixing time by 0.85 times, which proves the potential of microfluidic field strategy in enhancement and scale-up of liquid-liquid homogeneous chemical process. 展开更多
关键词 Mixing efficiency Chemical process intensification Scale up REACTOR Computational fluid dynamics(CFD) Numerical simulation
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Phosphorus speciation,transformation and benthic processes with implications for environmental impacts in the aquaculture area of Rushan Bay
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作者 Yao Feng Jun Liu +4 位作者 Aijun Zhang Yibin Wang Lu Wang Zongqing Lv Xiangbin Ran 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第8期99-112,共14页
Phosphorus(P)is an essential nutrient for many organisms in the ocean,which plays a central role in the stability of ecosystems and the evolution of the environment.The distribution,occurrence and source-sink process ... Phosphorus(P)is an essential nutrient for many organisms in the ocean,which plays a central role in the stability of ecosystems and the evolution of the environment.The distribution,occurrence and source-sink process of P in offshore waters are highly influenced by mariculture activities.P transformation in water-sediment system is the key process in P cycling,however,the mechanism is poorly documented in the coastal sea which is influenced by human activities.Based on the comprehensive surveys in the adjacent waters outside Rushan Bay in May,July and August 2014 and February 2015,the form and transformation of P in the suspended particulate matter(SPM)and surface sediment were analyzed.The results showed that contents of total P,authigenic P and organic P of SPM increased with the increase in distance from the shoreline off Rushan Bay,and the detrital-P decreased.The partition coefficient of P between water and SPM was related to the chemical activity of different forms of P,and a higher reactivity of inorganic P associated with SPM was observed.Hypoxia induced by mariculture changes the distribution and morphological composition of P in SPM and sediment in this typical aquaculture area,which can result in a conversion of sink to source of P in the sediment,thereby having a significant impact on the regional nutrient budget and associated with eutrophication. 展开更多
关键词 phosphorus speciation TRANSFORMATION benthic process AQUACULTURE Rushan Bay
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Effects on Sedimentary Processes via Upper Triassic Climate Forcing Caused by Multiple Impacting and Large Igneous Provinces (LIP)-Rifting/Degassing: Jordanian Platform/Arabian Plate and Germanic Basin/Central Europe
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作者 Werner Schneider Elias Salameh 《Open Journal of Geology》 CAS 2023年第2期136-170,共35页
Upper Triassic sedimentary systems of both the Arabian Plate and the Germanic Basin reveal climate- and plate tectonic-forced effects through certain time-intervals experienced by architectural elements, lithofacies t... Upper Triassic sedimentary systems of both the Arabian Plate and the Germanic Basin reveal climate- and plate tectonic-forced effects through certain time-intervals experienced by architectural elements, lithofacies types, unconformities, flash flood deposits, maximum flooding surfaces/sequence boundary (MFS/SB), mineralogy, and isotope anomalies. Further, Moon recession and changes of Earth’s rotation velocity (core/mantle boundary) are associated with multiple impacting and large igneous provinces/Mid Oceanic Ridge Basalt, LIP/MORB-rifting/degassing. While acidification (by degassing, sturz-rain) does influence tectosilicates and carbonates, montmorillonite represents a key mineral as transformation of volcanic/impact glass (Tephra) to be found as co-components in and in certain pelite units as “boundary clay-suspicions” (mixture of eolian paleoloess, pelite, paleosol, and tephra → tuffite). Obviously, unconformities and sequence boundaries of both study areas separate and dislocate interrupted ∂<sup>13</sup>C and <sup>87</sup>Sr/<sup>86</sup>Sr-data groups along the isotope curves. Both Proto-Arctic Ocean rifting/degassing comprising kimberlitic pyroclastic eruptions and Neotethys rifting/degassing as well as multiple impacting played the most important role during the Norian, followed by the incipient Central Atlantic Magmatic Provinces rifting since the Rhaetian. The following associations are encountered and dealt with in this study: Sequence boundaries-∂<sup>13</sup>C, maximum flooding surfaces-(FUCs)-∂<sup>13</sup>C, unconformities-plate motion, tephra-pelite-tuffite-montmorillonite. Norian: maximum flooding surfaces (MFSs)-“paleosol”/boundary clay?-rifting-volcanism, Moon/Earth data change. So the Norian (~221 - 206 Ma) hosts anomalous “amalgamated maximum flooding surfaces (MFSs)”, amalgamated paleosol (Jordanian Platform), multiple impacting (~219 - 214 Ma), the maximum opening of the Proto-Arctic Ocean (PAO) (~230 - 200 Ma), Neo-Tethys (NT)-subvolcanic (sills, dikes) in the NE Dead Sea area prior the Rhaetian, and a significant change of Earth/Moon relation data. The study concludes that rare and extreme events are very strongly shaping the geologic constellations in the Earth System. 展开更多
关键词 Endogenic and Impact Drivers Sedimentary Effects Interplay Processing Event-Stratigraphy
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Progress in Processes and Catalysts for Dehydrogenation of Cyclohexanol to Cyclohexanone
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作者 Jing Gong Shixin Hou +1 位作者 Yue Wang Xinbin Ma 《Transactions of Tianjin University》 EI CAS 2023年第3期196-208,共13页
The dehydrogenation of cyclohexanol to cyclohexanone is a crucial industrial process in the production of caprolactam and adipic acid, both of which serve as important precursors in nylon textiles. This endothermic re... The dehydrogenation of cyclohexanol to cyclohexanone is a crucial industrial process in the production of caprolactam and adipic acid, both of which serve as important precursors in nylon textiles. This endothermic reaction is constrained by thermodynamic equilibrium and involves a complex reaction network, leading to a heightened focus on catalysts and process design. Copper-based catalysts have been extensively studied and exhibit exceptional low-temperature catalytic performance in cyclohexanol dehydrogenation, with some being commercially used in the industry. This paper specifically concentrates on research advancement concerning active species, reaction mechanisms, factors influencing product selectivity, and the deactivation behaviors of copper-based catalysts. Moreover, a brief introduction to the new processes that break thermodynamic equilibrium via reaction coupling and their corresponding catalysts is summarized here as well. These reviews may off er guidance and potential avenues for further investigations into catalysts and processes for cyclohexanol dehydrogenation. 展开更多
关键词 CYCLOHEXANOL DEHYDROGENATION CYCLOHEXANONE Copper-based catalyst Reaction coupling processes
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Peri-Net-Pro: the neural processes with quantified uncertainty for crack patterns
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作者 M.KIM G.LIN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第7期1085-1100,共16页
This paper develops a deep learning tool based on neural processes(NPs)called the Peri-Net-Pro,to predict the crack patterns in a moving disk and classifies them according to the classification modes with quantified u... This paper develops a deep learning tool based on neural processes(NPs)called the Peri-Net-Pro,to predict the crack patterns in a moving disk and classifies them according to the classification modes with quantified uncertainties.In particular,image classification and regression studies are conducted by means of convolutional neural networks(CNNs)and NPs.First,the amount and quality of the data are enhanced by using peridynamics to theoretically compensate for the problems of the finite element method(FEM)in generating crack pattern images.Second,case studies are conducted with the prototype microelastic brittle(PMB),linear peridynamic solid(LPS),and viscoelastic solid(VES)models obtained by using the peridynamic theory.The case studies are performed to classify the images by using CNNs and determine the suitability of the PMB,LBS,and VES models.Finally,a regression analysis is performed on the crack pattern images with NPs to predict the crack patterns.The regression analysis results confirm that the variance decreases when the number of epochs increases by using the NPs.The training results gradually improve,and the variance ranges decrease to less than 0.035.The main finding of this study is that the NPs enable accurate predictions,even with missing or insufficient training data.The results demonstrate that if the context points are set to the 10th,100th,300th,and 784th,the training information is deliberately omitted for the context points of the 10th,100th,and 300th,and the predictions are different when the context points are significantly lower.However,the comparison of the results of the 100th and 784th context points shows that the predicted results are similar because of the Gaussian processes in the NPs.Therefore,if the NPs are employed for training,the missing information of the training data can be supplemented to predict the results. 展开更多
关键词 neural process(NP) PERIDYNAMICS crack pattern molecular dynamic(MD)simulation machine learning Gaussian process regression convolutional neural network(CNN)
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Processes for the Clarification of the Crude Oil of Baobab Seeds Extracted by Pressing on Activated Carbon Elaborated from the Capsules of the Fruit (Adansonia digitata L.)
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作者 Edouard Mbarick Ndiaye Alioune Sow +9 位作者 Kalidou Ba Mouhamed Ndoye Yousra El Idrissi Seyni Ndiaye Hamza El Moudden Papa Guedel Faye Hicham Harhar Nicolas Ayessou Mohamed Tabyaoui Mady Cisse 《Advances in Chemical Engineering and Science》 CAS 2023年第2期105-118,共14页
The baobab, Adansonia digitata L. plays an important role in the economy of local populations. The oil from the seeds of the baobab fruit is nowadays highly prized because of its numerous cosmetic and therapeutic appl... The baobab, Adansonia digitata L. plays an important role in the economy of local populations. The oil from the seeds of the baobab fruit is nowadays highly prized because of its numerous cosmetic and therapeutic applications and its composition of unsaturated fatty acids, sterols and tocopherols. However, unlike refined oils, locally extracted baobab oil has not undergone purification operations to ensure its quality. Only a filtration on special cloths is carried out after decantation. Indeed, the oil obtained after pressing is cloudy because of the presence of various impurities. It therefore requires treatment operations to make it more attractive and of higher quality. Therefore, in order to provide innovative solutions to local companies to improve the quality of vegetable oils, a study of clarification (treatment) of crude oil is necessary. An experimental device has been developed in the laboratory. It includes a glass column and a filter bed of dune sand and activated carbon. This study has shown the efficiency of the experimental device. Indeed, the activated carbon, thanks to its adsorbing power, has allowed a significant decrease in turbidity at the 5% threshold, from 14.61 NTU for the raw oil to 0.08 NTU for the oil filtered on 3% carbon and 0.033 NTU for the oil filtered on 5% carbon. That is to say an abatement higher than 95%. This decrease in turbidity could be correlated with the decrease in brown index from 187.39<sup>a</sup> for the initial crude oil to 128.53<sup>d</sup> for the oil treated with 3% activated carbon versus 187.59<sup>a</sup> for the oil filtered on cloths. The lowest brown index was observed with the filtration using 5% activated carbon (35.99<sup>b</sup>). Thus, for the yellowness index, only the filtration on 5% charcoal allowed to obtain a significant decrease in yellowness. The yellowing index of the oil with 5% was 44.67<sup>b</sup> against 79.04<sup>a</sup> for the oil filtered with 3% activated carbon, 86.33<sup>a</sup> for the crude oil and 86.46<sup>a</sup> for the oil filtered on cloths. Finally, the oil sample treated with 5% activated carbon had the clearest clarity than the other samples with a clarity (L) equal to 97.98<sup>c</sup> against 95.63<sup>d</sup> for the oil treated with 3% carbon and 94.99<sup>b</sup> for the oil filtered on filter cloths. According to the results obtained, the experimental device made it possible to obtain a clearer baobab oil with a low brown index, thus improving the sensory quality of the oil. 展开更多
关键词 Activated Carbon Baobab Oil CLARIFICATION Filtration Process
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Rationale for Decision-Making Processes in Enhancement of Community Participation for Sustainable Mangrove Management in Lamu, Kenya
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作者 Jamila Ahmed Bessy Kathambi Robert Kibugi 《Open Journal of Ecology》 2023年第6期409-421,共13页
Decision-making is the process of deciding between two or more options in order to take the most appropriate and successful course of action in order to achieve sustainable mangrove management. However, the distinctiv... Decision-making is the process of deciding between two or more options in order to take the most appropriate and successful course of action in order to achieve sustainable mangrove management. However, the distinctiveness of mangrove as an ecosystem, and thus the attendant socio-economic and governance ramifications, causes the idea of decision making to become relatively distinct from other decision making process As a result, the purpose of this research was to evaluate the impact that community engagement plays in the decision-making process as it relates to the establishment of governance norms for sustainable mangrove management in Lamu County. In this study, a correlational research design was applied, and the researchers employed a mixed techniques approach. The target population was 296 respondents. The research used questionnaires and interviews to collect data. A descriptive statistical technique was utilized to perform an inspection and analysis on the data that was gathered. The findings indicated that having awareness about governance standards is beneficial during the process of making decisions. In addition, the findings demonstrated that respondents had the impression that the decision-making process was not done properly. On the other hand, the participants pointed out the positive aspects of the decision-making process and agreed that the participation of both gender was essential for the sustainable management of mangroves. Based on these data, it appeared that full community engagement in decision-making is necessary for sustainable management of mangrove forests. 展开更多
关键词 Community Engagement SUSTAINABILITY Decision Making Process Lamu
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