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Effects of the sand content of muddy water content on one-dimensional vertical infiltration characteristics and dense layer formation characteristics

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 172-179页

作者： Shouxuan Kang Liangjun fei Yun Zhong Lihua Liu State Key Laboratory of Eco-hydraulics in Northwest Arid Region Xi’an University of TechnologyXi’an 710048China Institute of Water Resources and Hydro-electric Engineering Xi’an University of TechnologyXi’an 710048China Engineering Research Center of Eco-environment in Three Gorges Reservoir Region Ministry of EducationChina Three Gorges UniversityYichang 443002HubeiChina School of Water Conservancy and Hydroelectric Power Hebei University of EngineeringHandan 056038HebeiChina

Muddy water irrigation,an effective water-saving irrigation method,has been widely used in the Yellow River Basin in *** investigate the effect of sand content on water infiltration and dense layer formation under one-dimensional vertical infiltration of muddy water,muddy water infiltration experiments were performed in the laboratory,and five sand contents of muddy water(S=0%,3%,6%,9%,and 12%)were *** were established to describe the relationship between the cumulative infiltration amount[I(t)]and the infiltration duration(t);the relationship among the migration distance of the wetting front(Z),S,and t;the thickness of the sedimentary layer[H(t)];and the relationship between S and *** results revealed that I(t)and Z decreased significantly with the increase of sand contents,while H(t)increased significantly with the increase of sand contents.I(t)and Z were in the range of 7 cm and 20 cm for each treatment,*** variation in I(t)with t fitted Kostiakov and Philip models,and the coefficients of determination were all greater than *** the increase in S,the infiltration coefficient gradually decreased,the infiltration index gradually increased,and the sorptivity gradually *** particle composition of the sedimentary layer was similar to that of the argillaceous sediment,and the content of particles with a size of less than 2 mm in the sedimentary layer was lower than that of the argillaceous *** with the original soil,the content of particles with a size of less than 0.05 mm and physical clay particles(diameter less than 0.01 mm)in the soil with an infiltration depth of 0-2 cm *** retention layer was from the topsoil to the infiltration depth of approximately 2 *** study can provide a scientific basis for further research on soil infiltration mechanisms under muddy water.

关键词： muddy water sand content dense layer cumulative infiltration wetting front transport deposit layer thickness

Dynamic Surface Backstepping Global Sliding Mode Control for CPS Based on NDO

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Journal of Harbin Institute of Technology(New Series) 2015年第1期22卷 73-78页

作者： fei Li Jianbo Hu Jun Wu Jianhao Wang Materiel Management & Safety Engineering College Air Force Engineering University Institute of Cyber-Systems and Control Zhejiang University Unit 93286 People's Liberation Army

Based on dynamic surface control and the nonlinear disturbance observer technique,it proposes a nonlinear adaptive backstepping global sliding mode control system for a typical cyber physical system( CPS)with aerodynamic coefficients and external disturbance uncertainties. The dynamic surface control technique can provide the capability which can solve the problem of "explosion of complexity"in backstepping sliding mode controllers. The nonlinear disturbance observers are employed to observe the arbitrary model uncertainties of nonlinear flight dynamic system. The global sliding mode control method is used to improve the response rate and the precision of the tracking. The simulation results show the effectiveness of the proposed control system.

关键词： cyber physical system disturbance uncertainties dy

Implementation of low-swing differential interface circuits for high-speed on-chip asynchronous interconnection

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Science in China(Series F) 2008年第7期51卷 975-984页

作者： QIAO fei YANG HuaZhong HUANG Gang WANG Hui NICS Group Department of Electronic Engineering Tsinghua University Beijing 100084 China

A novel low-swing interface circuit for high-speed on-chip asynchronous interconnection is proposed in this paper. It takes a differential level-triggered latch to recover digital signal with ultra low-swing voltage less than 50 mV, and the driver part of the interface circuit is optimized for low power using the driver-array method, With a capacity to work up to 500 MHz, the proposed circuit, which is simulated and fabricated using SMIC 0.18-pm 1.8-V digital CMOS technology, consumes less power than previously reported designs.

关键词： low power circuit low-swing interface differential signaling tapered-buffer interconnect asynchronous circuit

Ambient air temperature effects on the temperature of sewage sludge composting process

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Journal of Environmental Sciences 2005年第6期17卷 1004-1007页

作者： HUANG Qi-fei CHEN Tong-bin GAO Ding HUANG Ze-chun Chinese Research Academy of Environmental Sciences Beijing 100012 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Using data obtained with a full-scale sewage sludge composting facility, this paper studied the effects of ambient air temperature on the composting temperature with varying volume ratios of sewage sludge and recycled compost to bulking agent. Two volume ratios were examined experimentally, 1 ： 0 ： 1 and 3 ： 1 ： 2. The results show that composting temperature was influenced by ambient air temperature and the influence was more significant when composting was in the temperature rising process： composting temperature changed 2.4-6.5℃ when ambient air temperature changed 13℃. On the other hand, the influence was not significant when composting was in the high-temperature and/or temperature falling process： composting temperature changed 0.75-1.3℃ when ambient air temperature changed 8-15℃. Hysteresis effect was observed in composting temperature＇s responses to ambient air temperature. When the ventilation capability of pile was excellent（at a volume ratio of 1：0：1）, the hysteresis time was short and ranging 1.1-1.2 h. On the contrary, when the proportion of added bulking agent was low, therefore less porosity in the substrate（at a volume ratio of 3：1：2）, the hysteresis time was IonQ and ranging 1.9-3.1 h.

关键词： sewage sludge composting ambient air temperature hysteresis

Docking process on hybrid self-reconfigurable modular robots

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High Technology Letters 2017年第1期23卷 71-76页

作者：帅立国 Su Huizhe Zheng Liyuan fei Yanqiong School of Mechanical and Electrical Engineering Henan Institute of Science and Technology School of Mechanical Engineering Shanghai Jiaotong University

A novel hybrid self-reconfigurable modular robot is designed to finish the morphing action from line shape to hexagon shape. The robot is composed of many basic modules,each of which consists of a master module and a slave module in the shape of triangular prism. There are four connection ports on each basic module. For the master module there are two holes on each connection port,and for the slave one there are two pegs on each connection. The docking process between two neighboring basic modules is analyzed with a peg-in-hole mechanical structure. A small motion's method is presented and the contact forces are derived. According to the force/moment,the pose of a motion module should be adjusted to make two neighboring modules align and finish the docking ***,a simulation of 3 basic modules is shown to finish the morphing and docking process effectively. The system can finish the morphing task from the line shape to the hexagon shape.

关键词： self-reconfigurable robot morphing hybrid module

Tailored classification of portal vein thrombosis for liver transplantation:Focus on strategies for portal vein inflow reconstruction

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World Journal of Gastroenterology 2020年第21期26卷 2691-2701页

作者： fei Teng Ke-Yan Sun Zhi-Ren Fu Department of Liver Surgery and Organ Transplantation Changzheng HospitalNavy Medical UniversityShanghai 200003China

Portal vein thrombosis(PVT)is currently not considered a contraindication for liver transplantation(LT),but diffuse or complicated PVT remains a major surgical ***,we review the prevalence,natural course and current grading systems of PVT and propose a tailored classification of PVT in the setting of *** in liver transplant recipients is classified into three types,corresponding to three portal reconstruction strategies:Anatomical,physiological and *** I PVT can be removed via low dissection of the portal vein(PV)or thrombectomy;porto-portal anastomosis is then performed with or without an interposed vascular *** reconstruction used for type II PVT includes vascular interposition between mesenteric veins and PV,collateral-PV and splenic vein-PV ***-physiological reconstruction used for type III PVT includes cavoportal hemitransposition,renoportal anastomosis,portal vein arterialization and multivisceral *** portal reconstruction techniques were *** tailored classification system stratifies PVT patients by surgical complexity,risk of postoperative complications and long-term *** advocate using the tailored classification for PVT grading before LT,which will urge transplant surgeons to make a better preoperative planning and pay more attention to all potential strategies for portal *** verification in a large-sample cohort study is needed.

关键词： Portal vein thrombosis Liver transplantation Portal reconstruction Grading Anatomical Physiological Non-physiological

Trace determination of zirconium using anodic adsorptive voltammetry at a carbon paste electrode modified with multi-walled carbon nanotubes

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Chinese Science Bulletin 2008年第11期53卷 1665-1670页

作者： DENG PeiHong fei JunJie ZHANG Jun LI JuNan Department of Chemistry and Material Science Hengyang Normal University Hengyang 421008 China College of Chemistry Xiangtan University Xiangtan 411105 China

A carbon paste electrode modified with multi-walled carbon nanotubes (MWCNT) was prepared and the determination of ultra trace amount of zirconium based on the anodic adsorptive voltammetry of the zirconium-calcium-alizarin red S mix-polynuclear complex is described in this paper for the first time. The results showed that the sensitivity and the selectivity of the method are excellent. The second de-rivative linear scan voltammograms of the complex were recorded by polarographic analyzer from 200 to 1200 mV (vs. SCE) and it was found that the complex can be adsorbed on the surface of the electrode, yielding a peak at about 840 mV, corresponding to the oxidation of ARS in the complex. The peak cur-rent increases linearly with Zr (IV) concentration in the range of 6.0×10-12―6.0×10-11 mol·L-1 (accumu-lation time 120 s), 6.0×10-11―2.0×10-9 mol·L-1 (accumulation time 90 s) and 2.0×10-9―1.0×10-7 mol·L-1 (accumulation time 60 s) and the detection limit (S/N = 3) is 2.0×10-12 mol·L-1 (accumulation time 180 s). The procedure has been successfully applied to the determination of zirconium in the ore samples.

关键词：多壁碳纳米管纳米技术碳电极锆阳极吸附伏安法

The steady-state and dynamic simulation of cascade distillation system for the production of oxygen-18 isotope from water

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Chinese Journal of Chemical Engineering 2016年第8期24卷 979-988页

作者： Yunhu Gao Zhihong Xu Kejing Wu Xiaolu Wang Zhaojun Yu Weiyang fei Jiangsu Huayi Technology Co. Ltd. State Key Laboratory of Chemical Engineering Department of Chemical Engineering Tsinghua University China Construction Installation Engineering Co.Ltd

Accurate simulation of water distillation system for oxygen-18(18O) isotope separation is necessary to guide industrial practice, since both deuterium(D) and oxygen-18 isotope get enriched and interfere with each other. In the present work, steady-state and dynamic distillation models are established based on a classic method and a cascade distillation system with 5 towers is introduced to test the models. The theoretical expressions of separation factor αH/Dfor protium/deuterium and separation factor α^(16)O/^(18) *** oxygen-16/oxygen-18 were derived,with the existence of deuterium and oxygen-18, respectively. The results of the steady-state simulation by the classical method proposed in the present work agreed well with the results of the lumping method. The dynamic process could be divided into 5 stages. Impressively, a peak value of product withdraw was observed before the final steady state, which was resulted from the change of ^(16)O/^(18) O separation factor and isotope distribution. An interesting low concentration zone in the towers of T2–T5 existed at the beginning of the dynamic process and it required industrial evidence.

关键词： Oxygen-18 Deuterium Steady-state simulation Dynamic simulation Isotope separation

Recreating Musicality in Translatining Chinese Classical Poetry from Persepective of Creative Translation

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Recreating Musicality in Translatining Chinese Classical Poe...

作者： Suo fei 西安外国语大学

学位级别：硕士

中国古典汉语诗歌中语音修辞的使用使得汉语古诗具有独特的音韵美，而诗歌的音韵美也是诗歌区别于其他文学体裁的重要特征。众多学者关注并探索诗歌翻译中语言艺术的再现，而诗歌翻译中音韵美的再现，作为诗歌语言艺术再现的一部分，也... 详细信息

中国古典汉语诗歌中语音修辞的使用使得汉语古诗具有独特的音韵美，而诗歌的音韵美也是诗歌区别于其他文学体裁的重要特征。众多学者关注并探索诗歌翻译中语言艺术的再现，而诗歌翻译中音韵美的再现，作为诗歌语言艺术再现的一部分，也一直是学者不断探索的领域。学者多从押韵、节奏以及诗歌格律等方面去探讨汉诗英译中音韵美的再现方法，但从诗歌中语音修辞翻译的角度去研究汉诗英译音美再现方法的研究并不全面。本研究从许渊冲创译论视角，探索如何通过翻译汉语诗歌中的语音修辞来实现汉诗英译中音韵美的再现，进而为诗歌翻译中语言音韵美的传达提出方法和策略。创译论强调在目的语中再现原语读者的审美感受，强调要发挥译入语的优势，提倡译者在翻译中像原语作者一样创造文体美。本文通过分析汉语古诗中语音修辞的使用，总结出三方面音美效果:模拟自然声音之生动美，诗行内押韵之和谐美;以及音节重叠之韵律美。接着采用对比分析法，分析对比英汉语音修辞在音韵美表达上的相似之处，总结英语语音修辞在音美表达上与汉语语音修辞的相似性，为发挥译入语的优势找到根据，然后通过分析与研究大量前人汉诗英译译例，译例多来自文学诗歌翻译领域知名译者如詹姆斯.理雅阁、伯顿.华岑、亚瑟.韦利以及我国诗歌翻译大家许渊冲，进而总结出用英语诗歌中常见语音修辞手段再现汉语诗歌中语音修辞音韵美的方法。研究得出以下结论：汉诗英译中，英语拟声词、重复、头韵的修辞手法可再现汉语古诗中的摹声词的音美效果;英语头韵、元音韵、尾韵、辅音韵等修辞手法可再现汉语古诗中双声叠韵的音韵美;英语重复、头韵可再现汉语古诗中叠音词的音美效果;英译汉诗中某一语音修辞音韵美在翻译中的流失可通过使用其他英语语音修辞来创造另一种音韵美来弥补。该研究将可为后续汉诗英译音美再现的相关研究提供参考。

关键词：诗歌翻译诗歌音美许渊冲创美论对比研究英语语音修辞汉语语音修辞