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Unveiling evapotranspiration patterns and energy balance in a subalpine forest of the Qinghai-Tibet Plateau:observations and analysis from an eddy covariance system
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作者 Niu Zhu Jinniu Wang +6 位作者 Dongliang Luo Xufeng Wang Cheng Shen Ning Wu Ning Zhang Binghui Tian Aihong Gai 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第3期175-188,共14页
Evapotranspiration is an important parameter used to characterize the water cycle of ecosystems.To under-stand the properties of the evapotranspiration and energy balance of a subalpine forest in the southeastern Qing... Evapotranspiration is an important parameter used to characterize the water cycle of ecosystems.To under-stand the properties of the evapotranspiration and energy balance of a subalpine forest in the southeastern Qinghai-Tibet Plateau,an open-path eddy covariance system was set up to monitor the forest from November 2020 to October 2021 in a core area of the Three Parallel Rivers in the Qing-hai-Tibet Plateau.The results show that the evapotranspira-tion peaked daily,the maximum occurring between 11:00 and 15:00.Environmental factors had significant effects on evapotranspiration,among them,net radiation the greatest(R^(2)=0.487),and relative humidity the least(R^(2)=0.001).The energy flux varied considerably in different seasons and sensible heat flux accounted for the main part of turbulent energy.The energy balance ratio in the dormant season was less than that in the growing season,and there is an energy imbalance at the site on an annual time scale. 展开更多
关键词 EVAPOTRANSPIRATION Energy balance Subalpine forest Three Parallel Rivers region Southeast Qinghai-Tibet Plateau
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Harmonic balance simulation of the influence of component uniformity and reliability on the performance of a Josephson traveling wave parametric amplifier
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作者 郑煜臻 熊康林 +1 位作者 冯加贵 杨辉 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期339-343,共5页
A Josephson traveling wave parametric amplifier(JTWPA),which is a quantum-limited amplifier with high gain and large bandwidth,is the core device of large-scale measurement and control systems for quantum computing.A ... A Josephson traveling wave parametric amplifier(JTWPA),which is a quantum-limited amplifier with high gain and large bandwidth,is the core device of large-scale measurement and control systems for quantum computing.A typical JTWPA consists of thousands of Josephson junctions connected in series to form a transmission line and hundreds of shunt LC resonators periodically loaded along the line for phase matching.Because the variation of these capacitors and inductors can be detrimental to their high-frequency characteristics,the fabrication of a JTWPA typically necessitates precise processing equipment.To guide the fabrication process and further improve the design for manufacturability,it is necessary to understand how each electronic component affects the amplifier.In this paper,we use the harmonic balance method to conduct a comprehensive study on the impact of nonuniformity and fabrication yield of the electronic components on the performance of a JTWPA.The results provide insightful and scientific guidance for device design and fabrication processes. 展开更多
关键词 Josephson traveling wave parametric amplifier(JTWPA) harmonic balance method YIELDS UNIFORMITY
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Linker aggregation engineering of TADF materials to tune carrierbalance for highly efficient organic LEDs with long operationallifetime
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作者 Zhen Zhang Rongrong Xia +8 位作者 Ke Wang Youjun Wu Panpan Zang Xuemin Gan Zhangcheng Liao Bin Wei Peng Wu Stefan Bräse Zixing Wang 《Aggregate》 EI CAS 2024年第5期385-393,共9页
Thermally activated delayedfluorescence(TADF)molecules are regarded as promis-ing materials for realizing high-performance organic light-emitting diodes(OLEDs).The connecting groups between donor(D)and acceptor(A)units... Thermally activated delayedfluorescence(TADF)molecules are regarded as promis-ing materials for realizing high-performance organic light-emitting diodes(OLEDs).The connecting groups between donor(D)and acceptor(A)units in D–A type TADF molecules could affect the charge transfer and luminescence performance of TADF materials in aggregated states.In this work,we design and synthesize four TADF molecules using planar and twisted linkers to connect the aza-azulene donor(D)and triazine acceptor(A).Compared with planar linkers,the twisted ones(Az-NP-T and Az-NN-T)can enhance A–A aggregation interaction between adjacent molecules to balance hole and electron density.As a result,highly efficient and stable deep-red top-emission OLEDs with a high electroluminescence efficiency of 57.3%and an impressive long operational lifetime(LT_(95)∼30,000 h,initial luminance of 1000 cd m^(-2))are obtained.This study provides a new strategy for designing more effi-cient and stable electroluminescent devices through linker aggregation engineering in donor–acceptor molecules. 展开更多
关键词 acceptor stacking balanced carrier transfer host materials long device lifetime thermally activated delayedfluorescence
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Rolling Decision Model of Thermal Power Retrofit and Generation Expansion Planning Considering Carbon Emissions and Power Balance Risk
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作者 Dong Pan Xu Gui +3 位作者 Jiayin Xu Yuming Shen Haoran Xu Yinghao Ma 《Energy Engineering》 EI 2024年第5期1309-1328,共20页
With the increasing urgency of the carbon emission reduction task,the generation expansion planning process needs to add carbon emission risk constraints,in addition to considering the level of power adequacy.However,... With the increasing urgency of the carbon emission reduction task,the generation expansion planning process needs to add carbon emission risk constraints,in addition to considering the level of power adequacy.However,methods for quantifying and assessing carbon emissions and operational risks are lacking.It results in excessive carbon emissions and frequent load-shedding on some days,although meeting annual carbon emission reduction targets.First,in response to the above problems,carbon emission and power balance risk assessment indicators and assessment methods,were proposed to quantify electricity abundance and carbon emission risk level of power planning scenarios,considering power supply regulation and renewable energy fluctuation characteristics.Secondly,building on traditional two-tier models for low-carbon power planning,including investment decisions and operational simulations,considering carbon emissions and power balance risks in lower-tier operational simulations,a two-tier rolling model for thermal power retrofit and generation expansion planning was established.The model includes an investment tier and operation assessment tier and makes year-by-year decisions on the number of thermal power units to be retrofitted and the type and capacity of units to be commissioned.Finally,the rationality and validity of the model were verified through an example analysis,a small-scale power supply system in a certain region is taken as an example.The model can significantly reduce the number of days of carbon emissions risk and ensure that the power balance risk is within the safe limit. 展开更多
关键词 Carbon emission risk power balance risk thermal power retrofit generation expansion planning
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Linking Perceived Risk of Public Health Emergency to Psychological Distress among Chinese College Students: The Chain Mediation Role of Balanced Time Perspective and Negative Coping Styles
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作者 Biru Chang Shengqiang Zhu +1 位作者 Qian Xie Yanghui Dai 《International Journal of Mental Health Promotion》 2024年第8期599-610,共12页
Background:With public health emergencies(PHE)worldwide increasing,the perceived risk of PHE has been one of the critical factors influencing college students’psychological distress.However,the mechanisms by which th... Background:With public health emergencies(PHE)worldwide increasing,the perceived risk of PHE has been one of the critical factors influencing college students’psychological distress.However,the mechanisms by which the perceived risk of PHE affects college students’psychological distress are not clear.The study’s purpose was to investigate the mediation roles of deviation from a balanced time perspective(DBTP)and negative coping styles between the perceived risk of PHE and psychological distress.Methods:A convenience sampling method was used to survey 1054 Chinese college students with self-reporting.Data was collected using the Public Risk Perception Scale(PRPS),the Zimbardo Time Perspective Inventory(ZTPI),the Simplified Coping Style Questionnaire(SCSQ),the PHE Anxiety Scale,and the Chinese version of the Patient Health Questionnaire(PHQ).The associations between the perceived risk of PHE,DBTP,negative coping styles,and psychological distress were clarified using the correlation analysis.Additionally,the mediating roles of DBTP and negative coping styles between the perceived risk of PHE and psychological distress were investigated using a structural equation model.Results:The findings revealed low to moderate correlations between the variables studied.Students’perceived risk of PHE was a positive predictor of their psychological distress(b=0.219,p<0.01).DBTP and negative coping styles played chain mediation roles between them with the effect being 0.009 and a 95%Boot CI of[0.003,0.023].This chain mediation model had an excellent fit index(χ^(2)/df=4.732,CFI=0.973,TLI=0.930,RMSEA=0.048,SRMR=0.047).Conclusion:These findings showed how the perceived risk of PHE affected college students’psychological distress.Specifically,these results suggested that improving students’mental ability to switch effectively among different time perspectives depending on task features and situational considerations and reducing their negative coping styles might be effective ways to promote their mental health. 展开更多
关键词 Perceived risk of public health emergency balanced time perspective negative coping styles psychological distress college students China
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基于BCD工艺的LIN总线收发器设计
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作者 杨雨辰 王志亮 +1 位作者 孙力 谭庶欣 《固体电子学研究与进展》 CAS 2024年第1期50-58,共9页
针对汽车内部复杂的控制节点与严苛的通讯环境,设计了一款抑制电磁干扰的局域互联网络(Local interconnect network, LIN)总线收发器芯片。基于90 nm BCD高压工艺,采用双向静电放电保护、分段电流驱动、共源级隔离驱动以及总线反馈技术... 针对汽车内部复杂的控制节点与严苛的通讯环境,设计了一款抑制电磁干扰的局域互联网络(Local interconnect network, LIN)总线收发器芯片。基于90 nm BCD高压工艺,采用双向静电放电保护、分段电流驱动、共源级隔离驱动以及总线反馈技术提高系统可靠性。测试结果表明芯片性能符合LIN总线物理层协议规范要求,实现了高低电压域的转换;同时具有良好的抗干扰能力,信号占空比最大变化仅为2.8%,电磁辐射比标准限制值低28 dBμV,达到车用LIN总线通讯相关标准要求。 展开更多
关键词 lin总线 收发器 斜率控制 BCD工艺 电磁干扰 ESD保护
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Hybrid model for BOF oxygen blowing time prediction based on oxygen balance mechanism and deep neural network 被引量:2
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作者 Xin Shao Qing Liu +3 位作者 Zicheng Xin Jiangshan Zhang Tao Zhou Shaoshuai Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期106-117,共12页
The amount of oxygen blown into the converter is one of the key parameters for the control of the converter blowing process,which directly affects the tap-to-tap time of converter. In this study, a hybrid model based ... The amount of oxygen blown into the converter is one of the key parameters for the control of the converter blowing process,which directly affects the tap-to-tap time of converter. In this study, a hybrid model based on oxygen balance mechanism (OBM) and deep neural network (DNN) was established for predicting oxygen blowing time in converter. A three-step method was utilized in the hybrid model. First, the oxygen consumption volume was predicted by the OBM model and DNN model, respectively. Second, a more accurate oxygen consumption volume was obtained by integrating the OBM model and DNN model. Finally, the converter oxygen blowing time was calculated according to the oxygen consumption volume and the oxygen supply intensity of each heat. The proposed hybrid model was verified using the actual data collected from an integrated steel plant in China, and compared with multiple linear regression model, OBM model, and neural network model including extreme learning machine, back propagation neural network, and DNN. The test results indicate that the hybrid model with a network structure of 3 hidden layer layers, 32-16-8 neurons per hidden layer, and 0.1 learning rate has the best prediction accuracy and stronger generalization ability compared with other models. The predicted hit ratio of oxygen consumption volume within the error±300 m^(3)is 96.67%;determination coefficient (R^(2)) and root mean square error (RMSE) are0.6984 and 150.03 m^(3), respectively. The oxygen blow time prediction hit ratio within the error±0.6 min is 89.50%;R2and RMSE are0.9486 and 0.3592 min, respectively. As a result, the proposed model can effectively predict the oxygen consumption volume and oxygen blowing time in the converter. 展开更多
关键词 basic oxygen furnace oxygen consumption oxygen blowing time oxygen balance mechanism deep neural network hybrid model
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Nanopriming with selenium doped carbon dots improved rapeseed germination and seedling salt tolerance 被引量:1
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作者 Mohammad Nauman Khan Chengcheng Fu +7 位作者 Xiaohui Liu Yanhui Li Jiasen Yan Lin Yue Jiaqi Li Zaid Khan Lixiao Nie Honghong Wu 《The Crop Journal》 SCIE CSCD 2024年第5期1333-1343,共11页
Soil salinity is a big environmental issue affecting crop production.Although seed nanopriming has been widely used to improve seed germination and seedling growth under salinity,our knowledge about the underlying mec... Soil salinity is a big environmental issue affecting crop production.Although seed nanopriming has been widely used to improve seed germination and seedling growth under salinity,our knowledge about the underlying mechanisms is still insufficient.Herein,we newly synthesized selenium-doped carbon dots nanoparticles coated with poly acrylic acid(poly acrylic acid coated selenium doped carbon dots,PAA@Se-CDs)and used it to prime seeds of rapeseeds.The TEM(transmission electron microscope)size and zeta potential of PAA@Se-CDs are 3.8±0.2 nm and-30 mV,respectively.After 8 h priming,the PAA@Se-CDs nanoparticles were detected in the seed compartments(seed coat,cotyledon,and radicle),while no such signals were detected in the NNP(no nanoparticle control)group(SeO_2 was used as the NNP).Nanopriming with PAA@Se-CDs nanoparticles increased rapeseeds germination(20%)and seedling fresh weight(161%)under saline conditions compared to NNP control.PAA@Se-CDs nanopriming significantly enhanced endo-β-mannanase activities(255%increase,21.55μmol h^(-1)g^(-1)vs.6.06μmol h^(-1)g^(-1),at DAS 1(DAS,days after sowing)),total soluble sugar(33.63 mg g^(-1)FW(fresh weight)vs.20.23 mg g^(-1)FW)and protein contents(1.96μg g^(-1)FW vs.1.0μg g^(-1)FW)to support the growth of germinating seedlings of rapeseeds under salt stress,in comparison with NNP co ntrol.The respiration rate and ATP content were increased by 76%and 607%,respectively.The oxidative damage of salinity due to the overaccumulation of reactive oxygen species(ROS)was alleviated by PAA@Se-CDs nanopriming by increasing the antioxidant enzyme activities(SOD(superoxide dismutase),POD(peroxidase),and CAT(catalase)).Another mechanism behind PAA@Se-CDs nanopriming improving rapeseeds salt tolerance at seedling stage was reducing sodium(Na^(+))accumulation and improving potassium(K^(+))retention,hence increasing the K^(+)/Na^(+)ratio under saline conditions.Overall,our results not only showed that seed nanopriming with PAA@Se-CDs could be a good approach to improve salt tolerance,but also add more knowledge to the mechanism behind nanopriming-improved plant salt tolerance at germination and early seedling growth stage. 展开更多
关键词 PAA@Se-CDs Nanopriming Salt stress Antioxidant system K^(+)/Na^(+) balance ATP production
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A Multi-Object Genetic Algorithm for the Assembly Line Balance Optimization in Garment Flexible Job Shop Scheduling
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作者 Junru Liu Yonggui Lv 《Intelligent Automation & Soft Computing》 SCIE 2023年第8期2421-2439,共19页
Numerous clothing enterprises in the market have a relatively low efficiency of assembly line planning due to insufficient optimization of bottleneck stations.As a result,the production efficiency of the enterprise is... Numerous clothing enterprises in the market have a relatively low efficiency of assembly line planning due to insufficient optimization of bottleneck stations.As a result,the production efficiency of the enterprise is not high,and the production organization is not up to expectations.Aiming at the problem of flexible process route planning in garment workshops,a multi-object genetic algorithm is proposed to solve the assembly line bal-ance optimization problem and minimize the machine adjustment path.The encoding method adopts the object-oriented path representation method,and the initial population is generated by random topology sorting based on an in-degree selection mechanism.The multi-object genetic algorithm improves the mutation and crossover operations according to the characteristics of the clothing process to avoid the generation of invalid offspring.In the iterative process,the bottleneck station is optimized by reasonable process splitting,and process allocation conforms to the strict limit of the station on the number of machines in order to improve the compilation efficiency.The effectiveness and feasibility of the multi-object genetic algorithm are proven by the analysis of clothing cases.Compared with the artificial allocation process,the compilation efficiency of MOGA is increased by more than 15%and completes the optimization of the minimum machine adjustment path.The results are in line with the expected optimization effect. 展开更多
关键词 Assembly line balance topological order genetic algorithm compilation efficiency pre-production scheduling
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Regularity of Fluxes in Nonlinear Hyperbolic Balance Laws
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作者 Matania Ben-Artzi Jiequan Li 《Communications on Applied Mathematics and Computation》 2023年第3期1289-1298,共10页
This paper addresses the issue of the formulation of weak solutions to systems of nonlinear hyperbolic conservation laws as integral balance laws.The basic idea is that the“meaningful objects”are the fluxes,evaluate... This paper addresses the issue of the formulation of weak solutions to systems of nonlinear hyperbolic conservation laws as integral balance laws.The basic idea is that the“meaningful objects”are the fluxes,evaluated across domain boundaries over time intervals.The fundamental result in this treatment is the regularity of the flux trace in the multi-dimensional setting.It implies that a weak solution indeed satisfies the balance law.In fact,it is shown that the flux is Lipschitz continuous with respect to suitable perturbations of the boundary.It should be emphasized that the weak solutions considered here need not be entropy solutions.Furthermore,the assumption imposed on the flux f(u)is quite minimal-just that it is locally bounded. 展开更多
关键词 balance laws Hyperbolic conservation laws MULTI-DIMENSIONAL Discontinuous solutions Finite-volume schemes FLUX Trace on boundary
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高可靠LIN控制器IP的设计与实现
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作者 李小波 王祥莉 +2 位作者 赵鹏翔 韩明 林剑东 《现代电子技术》 北大核心 2024年第22期30-36,共7页
LIN虽然为传统总线,但仍大量应用在汽车、智能家居和工业控制等领域。基于此,设计一种高可靠LIN控制器IP。基于AMBA APB3.0标准接口的IP不仅实现了LIN协议规定的数据收发、网络管理等功能,还增加了大量可靠性和安全性相关功能,如错误监... LIN虽然为传统总线,但仍大量应用在汽车、智能家居和工业控制等领域。基于此,设计一种高可靠LIN控制器IP。基于AMBA APB3.0标准接口的IP不仅实现了LIN协议规定的数据收发、网络管理等功能,还增加了大量可靠性和安全性相关功能,如错误监测、看门狗、环回自测试、显性电平监控等,通过这些可靠性措施使得IP达到ASIL-B级技术指标要求。针对IP搭建仿真验证环境,完成了SoC级仿真和FPGA原型验证,并基于国内某流片厂商110 nm工艺,完成了逻辑综合,生成了Verilog格式的网表文件。通过测试和逻辑综合分析得出:所提出的控制器IP性能满足协议和设计需求,在110 nm三温三压极限条件最高频率可达625 MHz,逻辑单元约为5 950,等效逻辑门约为10 554,面积为34 676μm2。该IP功能优于对比文献,可直接集成到微控制器MCU、SoC和FPGA设计中,减少设计周期和产品上市时间。 展开更多
关键词 lin总线 控制器IP 高可靠性 安全功能 逻辑综合 SoC仿真 FPGA原型验证
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LIN28A/B在肿瘤发生发展中的作用研究进展
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作者 张译文 黄琴 +2 位作者 吴艳芸 孙月 韦永龙 《遗传》 CAS CSCD 北大核心 2024年第6期452-465,共14页
LIN28A及其同源蛋白LIN28B是高度保守的RNA结合蛋白,在胚胎早期发育、体细胞重编程、葡萄糖代谢以及肿瘤发生发展中具有重要作用。LIN28A/B在乳腺癌等恶性肿瘤中高表达,在肿瘤的起始、维持和转移中均发挥重要作用,并与预后不良相关。研... LIN28A及其同源蛋白LIN28B是高度保守的RNA结合蛋白,在胚胎早期发育、体细胞重编程、葡萄糖代谢以及肿瘤发生发展中具有重要作用。LIN28A/B在乳腺癌等恶性肿瘤中高表达,在肿瘤的起始、维持和转移中均发挥重要作用,并与预后不良相关。研究表明,LIN28A/B主要通过抑制let-7s等microRNA和直接靶向mRNA的方式发挥调控作用。本文主要综述了LIN28A/B在肝癌、乳腺癌、结直肠癌等恶性肿瘤中的功能及其分子调控机制,以期为进一步研究LIN28A/B的作用机制及其在临床治疗中的可能应用提供理论参考。 展开更多
关键词 lin28A lin28B let-7 miRNA 肿瘤发生发展 治疗靶点
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Theoretical study of particle and energy balance equations in locally bounded plasmas
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作者 Hyun-Su JUN Yat Fung TSANG +1 位作者 Jae Ok YOO Navab SINGH 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第12期89-98,共10页
In this study,new particle and energy balance equations have been developed to predict the electron temperature and density in locally bounded plasmas.Classical particle and energy balance equations assume that all pl... In this study,new particle and energy balance equations have been developed to predict the electron temperature and density in locally bounded plasmas.Classical particle and energy balance equations assume that all plasma within a reactor is completely confined only by the reactor walls.However,in industrial plasma reactors for semiconductor manufacturing,the plasma is partially confined by internal reactor structures.We predict the effect of the open boundary area(A′_(L,eff))and ion escape velocity(u_(i))on electron temperature and density by developing new particle and energy balance equations.Theoretically,we found a low ion escape velocity(u_(i)/u_(B)≈0.2)and high open boundary area(A′_(L,eff)/A_(T,eff)≈0.6)to result in an approximately 38%increase in electron density and an 8%decrease in electron temperature compared to values in a fully bounded reactor.Additionally,we suggest that the velocity of ions passing through the open boundary should exceedω_(pi)λ_(De)under the condition E^(2)_(0)?(Φ/λ_(De))^(2). 展开更多
关键词 particle balance equation energy balance equation low temperature plasmas
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Multi-Model Approach for Assessing the Influence of Calibration Criteria on the Water Balance in Ouémé Basin
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作者 Aymar Yaovi Bossa Mahutin Aristide Oluwatobi Kpossou +1 位作者 Jean Hounkpè Félicien Djigbo Badou 《Journal of Water Resource and Protection》 CAS 2024年第3期207-218,共12页
Hydrological models are very useful tools for evaluating water resources, and the hydroclimatic hazards associated with the water cycle. However, their calibration and validation require the use of performance criteri... Hydrological models are very useful tools for evaluating water resources, and the hydroclimatic hazards associated with the water cycle. However, their calibration and validation require the use of performance criteria which choice is not straightforward. This paper aims to evaluate the influence of the performance criteria on water balance components and water extremes using two global rainfall-runoff models (HBV and GR4J) over the Ouémé watershed at the Bonou and Savè outlets. Three (3) Efficacy criteria (Nash, coefficient of determination, and KGE) were considered for calibration and validation. The results show that the Nash criterion provides a good assessment of the simulation of the different parts of the hydrograph. KGE is better for simulating peak flows and water balance elements than other efficiency criteria. This study could serve as a basis for the choice of performance criteria in hydrological modelling. 展开更多
关键词 Hydrological Modelling Performance Criteria Water balance Ouémé Basin
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CFD-PBM coupled modeling of the liquid-liquid dispersion characteristics and structure optimization for Kenics static mixer
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作者 Junhai Deng Shilin Lan +4 位作者 Juchang Wu Shenghua Du Weidong Liu Luchang Han Yefeng Zhou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第6期173-188,共16页
Kenics static mixers(KSM)are extensively used in industrial mixing-reaction processes by virtue of high mixing efficiency,low power homogenization and easy continuous production.Resolving liquid droplet size and its d... Kenics static mixers(KSM)are extensively used in industrial mixing-reaction processes by virtue of high mixing efficiency,low power homogenization and easy continuous production.Resolving liquid droplet size and its distribution and thus revealing the dispersion characteristics are of great significance for structural optimization and process intensification in the KSM.In this work,a computational fluid dynamics-population balance model(CFD-PBM)coupled method is employed to systematically investigate the effects of operating conditions and structural parameters of KSM on droplet size and its distribution,to further reveal the liquid-liquid dispersion characteristics.Results indicate that higher Reynolds numbers or higher dispersed phase volume fractions increase energy dissipation,reducing Sauter mean diameter(SMD)of dispersed phase droplets and with a shift in droplet size distribution(DSD)towards smaller size.Smaller aspect ratios,greater blade twist and assembly angles amplify shear rate,leading to smaller droplet size and a narrower DSD in the smaller range.The degree of impact exerted by the aspect ratio is notably greater.Notably,mixing elements with different spin enhance shear and stretching efficiency.Compared to the same spin,SMD becomes 3.7-5.8 times smaller in the smaller size range with a significantly narrower distribution.Taking into account the pressure drop and efficiency in a comprehensive manner,optimized structural parameters for the mixing element encompass an aspect ratio of 1-1.5,a blade twist angle of 180°,an assembly angle of 90°,and interlaced assembly of adjacent elements with different spin.This work provides vital theoretical underpinning and future reference for enhancing KSM performance. 展开更多
关键词 CFD Population balance Liquid-liquid dispersion Kenics static mixer
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Transverse momentum balance of dijets in Xe+Xe collisions at the LHC
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作者 Yao Li Shu-Wan Shen +1 位作者 Sa Wang Ben-Wei Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第7期137-146,共10页
We present a theoretical study of the medium modifications of the p_(T)balance (x_(J)) of dijets in Xe+Xe collisions at■.The initial production of dijets was carried out using the POWHEG+PYTHIA8 prescription,which ma... We present a theoretical study of the medium modifications of the p_(T)balance (x_(J)) of dijets in Xe+Xe collisions at■.The initial production of dijets was carried out using the POWHEG+PYTHIA8 prescription,which matches the next-toleading-order (NLO) QCD matrix elements with the parton shower (PS) effect.The SHELL model described the in-medium evolution of nucleus–nucleus collisions using a transport approach.The theoretical results of the dijet xJin the Xe+Xe collisions exhibit more imbalanced distributions than those in the p+p collisions,consistent with recently reported ATLAS data.By utilizing the Interleaved Flavor Neutralisation,an infrared-and-collinear-safe jet flavor algorithm,to identify the flavor of the reconstructed jets,we classify dijets processes into three categories:gluon–gluon (gg),quark–gluon (qg),and quark–quark (qq),and investigated the respective medium modification patterns and fraction changes of the gg,qg,and qq components of the dijet sample in Xe+Xe collisions.It is shown that the increased fraction of qg component at a small x_(J)contributes to the imbalance of the dijet;in particular,the q_(1)g_(2)(quark-jet-leading) dijets experience more significant asymmetric energy loss than the g_(1)q_(2)(gluon-jet-leading) dijets traversing the QGP.By comparing the■of inclusive,■ dijets in Xe+Xe collisions,we observe■.Moreover,ρ_(Xe),P_(b),the ratios of the nuclear modification factors of dijets in Xe+Xe to those in Pb+Pb,were calculated,which indicates that the yield suppression of dijets in Pb+Pb is more pronounced than that in Xe+Xe owing to the larger radius of the lead nucleus. 展开更多
关键词 Heavy-ion collisions Quark-gluon plasma Jet quenching Transverse momentum balance
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On the Use of Monotonicity-Preserving Interpolatory Techniques in Multilevel Schemes for Balance Laws
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作者 Antonio Baeza Rosa Donat Anna Martinez-Gavara 《Communications on Applied Mathematics and Computation》 EI 2024年第2期1319-1341,共23页
Cost-effective multilevel techniques for homogeneous hyperbolic conservation laws are very successful in reducing the computational cost associated to high resolution shock capturing numerical schemes.Because they do ... Cost-effective multilevel techniques for homogeneous hyperbolic conservation laws are very successful in reducing the computational cost associated to high resolution shock capturing numerical schemes.Because they do not involve any special data structure,and do not induce savings in memory requirements,they are easily implemented on existing codes and are recommended for 1D and 2D simulations when intensive testing is required.The multilevel technique can also be applied to balance laws,but in this case,numerical errors may be induced by the technique.We present a series of numerical tests that point out that the use of monotonicity-preserving interpolatory techniques eliminates the numerical errors observed when using the usual 4-point centered Lagrange interpolation,and leads to a more robust multilevel code for balance laws,while maintaining the efficiency rates observed forhyperbolic conservation laws. 展开更多
关键词 Hyperbolic balance laws Well-balanced schemes Multilevel schemes Harten's multiresolution
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Coupling Coordination Analysis of Cropland Intensification and Agroecosystem Services:Evidence from Loess Plateau in Shaanxi Province,China
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作者 FU Shaowu FU Mengyu QIU Menglong 《Chinese Geographical Science》 SCIE CSCD 2024年第3期401-419,共19页
One of the greatest challenges in the agroecosystem is to improve cropland intensification while preserving agroecosystem services.While many studies have investigated the effect of cropland intensification on agroeco... One of the greatest challenges in the agroecosystem is to improve cropland intensification while preserving agroecosystem services.While many studies have investigated the effect of cropland intensification on agroecosystem service,the interactive coupling and coordination among these factors remain largely unexplored.In view of this,this study performed a case study of the Loess Plateau in Shaanxi Province,China and constructed comprehensive evaluation models to quantify the cropland intensification and agroecosystem service in this area.Balance analysis and the coupling coordination degree model were used to evaluate the interactive relationship between cropland intensification and agroecosystem service,and statistical analysis and spatial autocorrelation were used to analyze the spatial characteristics and potential mechanism of the coupling coordination.Results show that both the cropland intensification and agroecosystem service in the study area were relatively low yet gradually increased from 2000 to 2020.Agroecosystem service lag was identified as the dominant unbalanced development type.Improving the supply capacity of agroecosystem services plays a key role in the balanced development of cropland in the Loess Plateau.The coupling coordination degree between cropland intensification and agroecosystem service ranges from basic coordination to serious incoordination.Therefore,cropland intensification practices in the area should be optimized to enhance this coordination degree.An upward trend was also observed in the coupling coordination degree from2000 to 2020.The withdrawal of marginal cropland in the Grain for Green program is one of the most important reasons for this trend,especially for the northern region.Around 83.6%of the high-high clusters are concentrated in the southern region of the Loess Plateau,whereas 70.5%of the low-low clusters are distributed in the northern region.These clustering characteristics are mainly attributed to the environmental suitability of these areas for agriculture and their degree of economic development. 展开更多
关键词 cropland intensification agroecosystem services balance analysis coupling coordination degree Loess Plateau China
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Regulating metal-acid double site balance on mesoporous SiO_(2)-Al_(2)O_(3) composite oxide for supercritical n-decane cracking
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作者 Liu-Ling Chen Jun Zhang +5 位作者 Chun-Guang Li Li-Qun Fei Bo Wang Chen-Qi Zhang Yi Jiao Jian-Li Wang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2881-2891,共11页
The balance between metal and acid sites directly affects the preparation of high-performance cracking catalysts with high heat sink and low coking.Nevertheless,how to control acid-metal sites balance and its relation... The balance between metal and acid sites directly affects the preparation of high-performance cracking catalysts with high heat sink and low coking.Nevertheless,how to control acid-metal sites balance and its relationship with cracking performance are reported scarcely.In this work,a series of Pt/Al_(2)O_(3)-SiO_(2) dual sites catalysts with different metal to acid active sites ratio(C_(M)/C_(SA))were constructed by ethanolassisted impregnation method and the impact on n-decane cracking under supercritical conditions was systematically and deeply investigated.The results showed that the conversion and carbon deposition increased gradually with varied C_(M)/C_(SA)and reached the balance at C_(M)/C_(SA)of 0.13.The proper ratio C_(M)/C_(SA)(0.13)can balance the deep dehydrogenation coking over metal active sites and high heat sink of cracking over acid active sites,the chemical heat sink reaches amazing 1.75 MJ/kg and carbon deposition is only22.03 mg/cm^(2) at 750℃.Meanwhile,the few metal sites at low C_(M)/C_(SA)and the few strong acid sites at high C_(M)/C_(SA)are the main factors limiting the cracking activity.Low C_(M)/C_(SA)limit the activation of C-H bond and deep dehydrogenation of coking precursor,resulting in relative low cracking activity and carbon deposition,while high C_(M)/C_(SA)limit the activation of C-C bond and increase the deep dehydrogenation.In this contribution,design and construction of metal-acid dual sites can not only provide the technical solution for the preparation of high heat sink and low coking cracking catalyst,but also deepen the understanding of the cracking path of hydrocarbon fuel. 展开更多
关键词 Metal-acid dual sites balance Catalytic cracking Hydrocarbon fuels Chemical heat sink Carbon deposition
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Multi-Objective Optimization of Multi-Product Parallel Disassembly Line Balancing Problem Considering Multi-Skilled Workers Using a Discrete Chemical Reaction Optimization Algorithm
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作者 Xiwang Guo Liangbo Zhou +4 位作者 Zhiwei Zhang Liang Qi Jiacun Wang Shujin Qin Jinrui Cao 《Computers, Materials & Continua》 SCIE EI 2024年第9期4475-4496,共22页
This work investigates a multi-product parallel disassembly line balancing problem considering multi-skilled workers.A mathematical model for the parallel disassembly line is established to achieve maximized disassemb... This work investigates a multi-product parallel disassembly line balancing problem considering multi-skilled workers.A mathematical model for the parallel disassembly line is established to achieve maximized disassembly profit and minimized workstation cycle time.Based on a product’s AND/OR graph,matrices for task-skill,worker-skill,precedence relationships,and disassembly correlations are developed.A multi-objective discrete chemical reaction optimization algorithm is designed.To enhance solution diversity,improvements are made to four reactions:decomposition,synthesis,intermolecular ineffective collision,and wall invalid collision reaction,completing the evolution of molecular individuals.The established model and improved algorithm are applied to ball pen,flashlight,washing machine,and radio combinations,respectively.Introducing a Collaborative Resource Allocation(CRA)strategy based on a Decomposition-Based Multi-Objective Evolutionary Algorithm,the experimental results are compared with four classical algorithms:MOEA/D,MOEAD-CRA,Non-dominated Sorting Genetic Algorithm Ⅱ(NSGA-Ⅱ),and Non-dominated Sorting Genetic Algorithm Ⅲ(NSGA-Ⅲ).This validates the feasibility and superiority of the proposed algorithm in parallel disassembly production lines. 展开更多
关键词 Parallel disassembly line balancing problem MULTI-PRODUCT multiskilled workers discrete chemical reaction optimization algorithm
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