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Evaporate prediction and compensation of intake port wall-wetting fuel film for spark ignition engines fueled with ethanol-gasoline blends

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第8期13卷 610-619页

作者： dong-wei yao Xin-chen LING Feng WU Institute of Power Machinery and Vehicular Engineering Zhejiang UniversityHangzhou 310027China

The fuel dynamic transfer process,including fuel injection,fuel film deposition and evaporation in the intake port,was analyzed for spark ignition(SI) engines with port fuel injection(PFI).The influence of wall-wetting fuel film,especially its evaporation rate,upon the air-fuel ratio of in-cylinder mixtures was also *** to the similarity principle,Fick's law,the ideal gas equation and the Gilliland correlation,an evaporate prediction model of wall-wetting fuel film was set up and an evaporate prediction based dynamic fuel film compensator was *** engine cold start tests,the wall-wetting temperature,which is the key input of the fuel film evaporate prediction model,was also modeled and *** with the experimental data of the evaporation characteristics of ethanol-gasoline blends and engine calibration tests,all the parameters of the wall-wetting fuel film evaporate prediction model used in the fuel film compensator were ***-wave disturbance tests of fuel injection showed that with the help of the fuel film compensator the response of the in-cylinder air-fuel ratio was significantly improved and the real air-fuel ratio always closely matched the expected *** fuel film compensator was then integrated into the final air-fuel ratio controller,and the engine tests showed that the air-fuel ratio control error was less than 2% in steady-state conditions,and less than 4% in transient *** fuel film compensator also showed good adaptability to different ethanol-gasoline blends.

关键词： Spark ignition (SI) engine Ethanol-gasoline blend Wall-wetting effect Evaporate prediction Fuel film compensation

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Event-driven process execution model for process virtual machine

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计算机集成制造系统 2012年第8期18卷 1675-1685页

作者： WU dong-yao wei Jun GAO Chu-shu DOU Wen-shen Technology Center for Software Engineering Institute of Software Chinese Academy of Sciences Beijing 100090 China

Current orchestration and choreography process engines only serve with dedicate process *** solve these problems,an Event-driven Process Execution Model(EPEM) was *** and mapping principles of the model were presented to guarantee the correctness and efficiency for process *** a case study,the EPEM descriptions of Web Services Business Process Execution Language(WS-BPEL) were represented and a Process Virtual Machine(PVM)-OncePVM was implemented in compliance with the EPEM.

关键词： business process modeling event-driven architecture process virtual machine service orchestration process execution language

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Gastroesophageal reflux in cirrhotic patients without esophageal varices

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World Journal of Gastroenterology 2011年第13期17卷 1753-1758页

作者： Jun Zhang Pei-Lin Cui dong Lv Shi-wei yao You-Qing Xu Zhao-Xu Yang Department of Gastroenterology Beijing TiantanHospital Capital Medical University Beijing 100050 China

AIM: To evaluate the esophageal motility and abnormal acid and bile reflux incidence in cirrhotic patients without esophageal varices (EV). METHODS: Seventy-eight patients with liver cirrhosis without EV confirmed by upper gastroesophageal endoscopy and 30 healthy control volunteers were prospectively enrolled in this study. All the patients were evaluated using a modified protocol including Child-Pugh score, upper gastrointestinal endoscopy, esophageal manometry, simultaneous ambulatory 24-h esophageal pH and bilirubin monitoring. All the patients and volunteers accepted the manometric study. RESULTS: In the liver cirrhosis group, lower esophageal sphincter pressure (LESP, 15.32 ± 2.91 mmHg), peristaltic amplitude (PA, 61.41 ± 10.52 mmHg), peristaltic duration (PD, 5.32 ± 1.22 s), and peristaltic velocity (PV, 5.22 ± 1.11 cm/s) were all significantly abnormal in comparison with those in the control group (P < 0.05), and LESP was negatively correlated with Child-Pugh score. The incidence of reflux esophagitis (RE) and pathologic reflux was 37.18% and 55.13%, respectively(vs control, P < 0.05). And the incidence of isolated abnormal acid reflux, bile reflux and mixed reflux was 12.82%, 14.10% and 28.21% in patients with liver cirrhosis without EV. CONCLUSION: Cirrhotic patients without EV presented esophageal motor disorders and mixed acid and bile reflux was the main pattern; the cirrhosis itself was an important causative factor.

关键词： Gastroesophageal reflux disease Liver cirrhosis Esophageal varices Esophageal manometry pH Bilirubin Monitoring

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清洁车用代用燃料焦炉气化学反应机理的简化与优化（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2017年第7期18卷 511-530页

作者： Hai-bin HE dong-wei yao Feng WU Institute of Power Machinery and Vehicular Engineering Zhejiang University Hangzhou 310027 China

目的:化学反应机理在内燃机计算流体动力学(CFD)仿真中起关键作用。基于敏感性分析与粒子群寻优算法,本文旨在提出适用于内燃机CFD仿真的焦炉气化学反应机理,为焦炉气在内燃机上的应用研究提供条件。创新点:1.结合敏感性分析与离子群寻... 详细信息

目的:化学反应机理在内燃机计算流体动力学(CFD)仿真中起关键作用。基于敏感性分析与粒子群寻优算法,本文旨在提出适用于内燃机CFD仿真的焦炉气化学反应机理,为焦炉气在内燃机上的应用研究提供条件。创新点:1.结合敏感性分析与离子群寻优算法,对化学反应机理参数进行了优化;2.建立了焦炉气化学反应机理,可准确仿真滞燃期、层流火焰速度、缸内压力变化和NOx生成。方法:1.根据简单碳氢燃料机理结构,搭建焦炉气化学反应机理(图1);2.通过敏感性分析,获得在燃烧中起关键作用的化学反应(图2和3);3.通过粒子群寻优算法,对上述关键化学反应的动力学参数进行优化(图4和5);4.通过数值仿真,验证机理的准确性(图6~13、16和17)。结论:1.根据敏感性定义,搭建的敏感性分析模型可准确地识别在燃烧过程中起关键作用的化学反应;2.基于粒子群寻优算法搭建的优化模型可对化学反应的动力学参数进行合理优化;3.优化后得到的焦炉气化学反应机理可准确预测滞燃期与层流火焰速度以及模拟内燃机缸内压力变化与NO_x生成。

关键词：焦炉气化学反应机理敏感性分析粒子群寻优内燃机计算流体力学仿真

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Impact of diesel emission fluid soaking on the performance of Cu-zeolite catalysts for diesel NH3-SCR systems

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2016年第4期17卷 325-334页

作者： dong-wei yao Feng WU Xin-lei WANG College of Energy Engineering Zhejiang University Hangzhou 310027 China Department of Agricultural and Biological Engineering University of Illinois at Urbana-Champaign Urbana 61801 USA

Diesel emission fluid （DEF） soaking and urea deposits on selective catalytic reduction （SCR） catalysts are critical issues for real diesel engine NH3-SCR systems. To investigate the impact of DEF soaking and urea deposits on SCR catalyst performance, fresh Cu-zeolite catalyst samples were drilled from a full-size SCR catalyst. Those samples were impregnated with DEF solutions and subsequently hydrothermally treated to simulate DEF soaking and urea deposits on real SCR catalysts during diesel engine operations. Their SCR performance was then evaluated in a flow reactor with a four-step test protocol. Test results show that the DEF soaking leached some Cu from the SCR catalysts and slightly reduced their Cu loadings. The loss of Cu and associated metal sites on the catalysts weakened their catalytic oxidation abilities and caused lower NO/NI-I3 oxidation and lower high-temperature N20 selectivity. Lower Cu loading also made the catalysts less active to the decomposition of surface ammonium nitrates and decreased low-temperature N20 selectivity. Cu loss during DEF impregnation released more acid sites on the surface of the catalysts and increased their acidities, and more NH3 was able to be adsorbed and involved in SCR reactions at medium and high temperatures. Due to lower NH3 oxidation and higher NH3 storage, the DEF-impregnated SCR catalyst samples showed higher NOx conversion above 400 ℃ compared with the non-soaked one. The negative impact of urea deposits during DEF impregnation was not clearly observed, because the high-temperature hydrothermal treatment helped to remove the urea deposits.

关键词： Diesel engine emission control Selective catalytic reduction (SCR) NOx reduction Cu-zeolite catalyst Diesel emission fluid (DEF) soaking

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柴油机Urea-SCR系统两相流及结晶的准一维数值模拟（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2016年第8期17卷 597-613页

作者： Xu-bo GAN dong-wei yao Feng WU Jia-wei DAI Lai wei Xing-wen LI Institute of Power Machinery and Vehicular Engineering Zhejiang University

目的:对柴油机Urea-SCR系统还原剂添加过程进行建模,探讨SCR系统中尿素结晶的主要影响因素,研究排气温度、流量和尿素水溶液喷射速率等对结晶成分、位置和总结晶量的作用规律。创新点:1.考虑喷雾和壁膜内尿素热解过程的差异,分别采用尿... 详细信息

目的:对柴油机Urea-SCR系统还原剂添加过程进行建模,探讨SCR系统中尿素结晶的主要影响因素,研究排气温度、流量和尿素水溶液喷射速率等对结晶成分、位置和总结晶量的作用规律。创新点:1.考虑喷雾和壁膜内尿素热解过程的差异,分别采用尿素的直接分解和化学反应动力学方法对喷雾和壁膜内的尿素热解过程进行描述;2.提出一维壁膜的概念,将尿素热解的化学反应动力学模型嵌入一维壁膜中,实现对结晶成分、位置和总结晶量的计算。方法:1.采用欧拉方法求解气相流动以及拉格朗日方法跟踪喷雾运动,通过附加源项方式实现气液两相之间的耦合;2.对尿素水溶液喷雾的蒸发、热解、碰壁和结晶等过程进行建模,并对仿真结果进行验证;3.对SCR系统中尿素结晶进行仿真分析,对排气温度、流量和尿素水溶液喷射速率等影响因素进行变参数研究。结论:1.排气温度的降低可以减小壁膜范围以及结晶量;结晶成分与温度密切相关:当温度较低时,结晶以尿素为主,随着温度升高,缩二脲和三聚氰酸开始逐渐形成;2.尿素水溶液喷射速率会影响壁膜范围以及结晶量,但其对结晶成分影响不大;3.排气流量的增大能够促进排气与液滴以及排气管壁之间的传热,从而减小壁膜范围以及结晶量。

关键词：选择性催化还原系统(SCR) 两相流壁膜结晶成分一维模型

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Boosting Oxygen Evolution Reaction Performance on NiFe‑Based Catalysts Through d‑Orbital Hybridization

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Nano-Micro Letters 2025年第1期17卷 281-292页

作者： Xing Wang wei Pi Sheng Hu Haifeng Bao Na yao wei Luo State Key Laboratory of New Textile Materials and Advanced Processing Technology Key Laboratory of New Textile Materials and Applications of Hubei ProvinceSchool of Materials Science and EngineeringWuhan Textile UniversityWuhan 430200People’s Republic of China College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072People’s Republic of China

Anion-exchange membrane water electrolyzers(AEMWEs)for green hydrogen production have received intensive attention due to their feasibility of using earth-abundant NiFe-based *** introducing a third metal into NiFe-based catalysts to construct asymmetrical M-NiFe units,the d-orbital and electronic structures can be adjusted,which is an important strategy to achieve sufficient oxygen evolution reaction(OER)performance in ***,the ternary NiFeM(M:La,Mo)catalysts featured with distinct M-NiFe units and varying d-orbitals are reported in this *** and theoretical calculation results reveal that the doping of La leads to optimized hybridization between d orbital in NiFeM and 2p in oxygen,resulting in enhanced adsorption strength of oxygen intermediates,and reduced rate-determining step energy barrier,which is responsible for the enhanced OER *** critically,the obtained NiFeLa catalyst only requires 1.58 V to reach 1 A cm^(−2) in an anion exchange membrane electrolyzer and demonstrates excellent long-term stability of up to 600 h.

关键词： NiFe-based catalysts d-orbital coupling Oxygen evolution reaction Anion exchange membrane electrolyzer

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Agricultural Mechanism of Spreading Catastrophe Risk in China and Legislation Conception

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Asian Agricultural Research 2011年第4期3卷 18-23,29页

作者： LI Xu-dong,SUN yao-wei Law Department of Southwest University,Chongqing 400716,China

This paper introduces agricultural catastrophe and its characteristics,and conducts comparative analysis on existing mechanism of spreading agricultural catastrophe risk,indicating that the mechanism of administrative remedy has the greatest efficiency and highest cost;the mechanism of social assistance has the lowest cost,but its efficiency is lowest and there are unstable factors;market mechanism,namely the insurance of agricultural catastrophe,is the rational choice of agricultural department in mechanism of risk *** paper analyzes the status quo of China's insurance of agricultural catastrophe,indicating that the main body of management in China's insurance of agricultural catastrophe is *** addition,the market demand is critically scanty,and insurance of agricultural catastrophe lacks external development *** gap of China's insurance law of agricultural catastrophe has become the greatest obstacle to the development of insurance of agricultural *** legislative purpose,basic principle,nature,main body of legal relations,management range,policy support,supervision and management and so on,the legislation conception of China's insurance of agricultural catastrophe is put forward.

关键词： Agricultural catastrophe Spreading mechanism Agric

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A Hybrid Approach for Pavement Crack Detection Using Mask R-CNN and Vision Transformer Model

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Computers, Materials & Continua 2025年第1期82卷 561-577页

作者： Shorouq Alshawabkeh Li Wu Daojun dong yao Cheng Liping Li Faculty of Engineering China University of GeosciencesWuhan430074China

Detecting pavement cracks is critical for road safety and infrastructure *** methods,relying on manual inspection and basic image processing,are time-consuming and prone to *** deep-learning(DL)methods automate crack detection,but many still struggle with variable crack patterns and environmental *** study aims to address these limitations by introducing the Masker Transformer,a novel hybrid deep learning model that integrates the precise localization capabilities of Mask Region-based Convolutional Neural Network(Mask R-CNN)with the global contextual awareness of Vision Transformer(ViT).The research focuses on leveraging the strengths of both architectures to enhance segmentation accuracy and adaptability across different pavement *** evaluated the performance of theMaskerTransformer against other state-of-theartmodels such asU-Net,TransformerU-Net(TransUNet),U-NetTransformer(UNETr),SwinU-NetTransformer(Swin-UNETr),You Only Look Once version 8(YoloV8),and Mask R-CNN using two benchmark datasets:Crack500 and *** findings reveal that the MaskerTransformer significantly outperforms the existing models,achieving the highest Dice SimilarityCoefficient(DSC),precision,recall,and F1-Score across both ***,the model attained a DSC of 80.04%on Crack500 and 91.37%on DeepCrack,demonstrating superior segmentation accuracy and *** high precision and recall rates further substantiate its effectiveness in real-world applications,suggesting that the Masker Transformer can serve as a robust tool for automated pavement crack detection,potentially replacing more traditional methods.

关键词： Pavement crack segmentation transportation deep learning vision transformer Mask R-CNN image segmentation

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Software-defined process-near-memory architecture using 3D hybrid bonding integration

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Science China(Information Sciences) 2025年第1期68卷 366-378页

作者： Anlin XU Chenchen DENG Jianfeng ZHU yao WANG Shaojun wei Leibo LIU School of Integrated Circuits Tsinghua University Beijing Institution of Tracking and Communication Technology Beijing National Research Center for Information Science and Technology Tsinghua University

With the unprecedented explosive growing amount of global data, the development of computing chips, which encounter bottlenecks such as power wall and memory wall, cannot satisfy the demanding requirement. This work proposes a software-defined process-near-memory(SDPNM) computing architecture implemented using 3D hybrid bonding *** software-defined chip architecture, featuring spatial computations and dynamic reconfiguration, innovates in a top-down manner to achieve high energy efficiency while maintaining flexibility after fabrication. The process-near-memory integration further advances the SDNPM chip in a bottom-up way to reduce the energy consumption of data movement while improving the bandwidth. Utilizing a relatively mature fabrication and bonding process can result in feasible solutions for both data-intensive and compute-intensive applications including digital signal processing and artificial intelligence. The logic die is fabricated in the SMIC 40 nm process and the DRAM die is fabricated in the PSMC 25 nm process. The hybrid bonding is implemented by XMC. The experimental results show that the energy efficiency of the proposed SDPNM chip is 33.1× better than the state-of-the-art FPGA ranging from 8.2× to 104.1×.

关键词： software-defined chips process near memory energy efficiency dynamic reconfiguration domain specific

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