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Virtual Design and Dynamic Simulation on Divider of Corn Harvester

2015年中国智能自动化学术会议

作者： Fatao Shi Yumei Ma Jinfei Yu Jinpeng Yu Ziyang Qu college of Automation Engineering Qingdao University Zibo Technician College

This paper addressed an adaptive fuzzy dynamic surface control(DSC)approach to speed regulation for induction motors.Fuzzy logic systems are used to approximate unknown nonlinear functions and the adaptive backstepping method is employed to construct controllers.By incorporating dynamic surface control technique into fuzzy control,we have developed an adaptive backstepping control design for induction motors.The proposed control method is able to overcome the problem of "explosion of complexity" inherent in the traditional backstepping design by introducing first-order low-pass filters.The adaptive fuzzy controllers guarantee the speed tracking error converges to a small neighborhood of the origin.Simulation results illustrate the effectiveness of the proposed approach.

关键词： Induction motors Dynamic surface control Fuzzy control Backstepping

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Journal of Zhouyi Research 2014年第2期 106-108页

作者： WU Xiuyuan (Shandong Water conservancy technician college ZiboShandong255130)

Thermal Deformation Behavior and Processing Map of a Novel CrFeNiSi_(0.15)Medium Entropy Alloy

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Acta Metallurgica Sinica(English Letters) 2023年第11期36卷 1870-1882页

作者： Hongbin Zhang Kang Chen Zhongwei Wang Haiping Zhou Chengcheng Shi Shengxue Qin Jie Liu Tingjun Lv Jian Xu college of Mechanical and Electronic Engineering Shandong University of Science and TechnologyQingdao266590China School of Mechanical Engineering Shandong University of TechnologyZibo255000China zibo Yuan Xu Metallurgical Machinery Co LtdZibo255120China

The thermal deformation behavior of a novel CrFeNiSi_(0.15)medium entropy alloy(MEA)was studied via isothermal compression experiments,with the processing parameter range of 900–1200℃and 0.001–1 s^(−1).According to experimental data,the modified constitutive equation had been obtained,which precisely predicted the flow behavior of CrFeNiSi_(0.15)MEA during thermal deformation.At the same time,the processing map was established on the basis of the dynamic material model(DMM)theory.According to the map,the optimal processing parameters were determined at 1130–1200℃/0.06–1 s−1,under which the power dissipation efficiency could reach above 34%.The peak efficiency was above 38%,which occurred at 1200℃/1 s^(−1).In such parameter,complete dynamic recrystallization(DRX)also occurred.The flow instability of CrFeNiSi_(0.15)MEA was estimated to occur at 900–985℃/0.12–1 s^(−1),which was shown as grain boundaries cracking.Furthermore,both the continuous DRX(CDRX)and discontinuous DRX(DDRX)occurred simultaneously during thermal deformation.Meanwhile,some twins were also newly formed during DRX process,most of which were primary twins.The occurrence of twinning was beneficial to promote the development of DRX behavior.

关键词： Medium entropy alloys Thermal deformation behavior Constitutive model Processing maps

Comprehensive evaluation of Korla fragrant pears and optimization of plucking time during the harvest period

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International Journal of Agricultural and Biological Engineering 2022年第3期15卷 242-250页

作者： Zhentao Wang Yurong Tang Xiaozhen Jin Yang Liu Hong Zhang Hao Niu Haipeng Lan college of Mechanical and Electrical Engineering Tarim UniversityAlar 843300XinjiangChina zibo Agricultural Machinery Service Center Zibo 255000ShandongChina

To optimize the harvest of Korla fragrant pears and to provide a theoretical basis for post-harvest processing,a total of 26 basic indices of Korla fragrant pears,including their morphology,quality,and softening age,were investigated.The harvest period ranged from August 22nd to October 6th,samples were collected every 5 d(totally 10 plucking days,indicated as H1-H10).The results indicated that changes in pectin content were the main causes of softening in fragrant pears.The scavenging of free radicals mainly occurred because of the collaborative effects of superoxide dismutase(SOD)and catalase(CAT).In the harvest periods H1-H3,the hardness,titratable acid(TA),chlorophyll content,density,and diameter of the stone cells,as well as the cellulose and hemicellulose content of the Korla fragrant pears were at their highest.During the periods H7-H10,the single-fruit weight,fruit horizontal and vertical diameter,color coordinates L,a*,b*,soluble-solids content(SSC),SOD activity,CAT activity,and water-soluble pectin were higher than in the other plucking periods.The highest vitamin C(VC)content and moderate values for a variety of indicators were observed during H3-H7.Variations in the Korla fragrant pears during H1-H3 mainly manifested through changes in softening-related parameters.During H3-H10,changes in the softening-related,aging-related,color-related,and quality indices had a dominant role.On this basis,some suggestions for the post-harvest processing of fragrant pears have been proposed.Fruit,during H1-H3,are suitable for transportation and storage;during H7-H10 are suitable for fresh-eating and further processing;and during H3-H7,exhibited moderate values for a variety of indicators and had the highest commercial value.This research provides a systematic evaluation of the characteristics of mature Korla fragrant pears during the harvest period and can form the basis for fruit quality control and processing of Korla fragrant pears.

关键词： Korla fragrant pear harvest period plucking time quality fruit maturity evaluation optimization

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A New Cooperative Distributed MPC Method Based on Reduction and Classification

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Chinese Journal of Electronics 2017年第3期26卷 564-572页

作者： WU Lan WANG Lei college of Electrical Engineering Henan University of Technology Department of Electrical Engineering Hangzhou First Technician College

To decrease the overlarge calculation induced by the centralized processing,a new cooperative distributed Model predictive control(MPC)method is proposed for large-scale systems with coupled dynamics.Reduction and classification are investigated by defining the influence degree to reduce the whole system and then to classify the reduced system into several subsystem groups.These groups are mutually decoupled,while there is relativity between these subsystems comprised in the same group.Centralized/cooperative and distributed MPC algorithms for each group are implemented to ensure the feasibility and the stability of the whole system.Meanwhile,for practical applications,the finite times interactive control strategy between different groups is adopted to compensate information loss brought by the reduced subsystem and realize the global cooperative distributed MPC.This algorithm significantly decreases the computational load,has better control performance.Simulations are given to illustrate the effectiveness of these developed algorithms.

关键词： Large-scale complex system Reduction and classification Influence degree Cooperative distributed Model predictive control(MPC)

Influence of Ionization Degrees on the Evolutions of Charged Particles in Atmospheric Plasma at Low Altitude

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Plasma Science and Technology 2012年第8期14卷 716-722页

作者：庞学霞邓泽超贾鹏英梁伟华李霞 college of Physics Science and Technology Hebei University Tangshan Labor technician college

A zero-dimensional model which includes 56 species of reactants and 427 reactions is used to study the behavior of charged particles in atmospheric plasmas with different ionization degrees at low altitude （near 0 km）. The constant coefficient nonlinear equations are solved by using the Quasi-steady-state approximation method. The electron lifetimes are obtained for afterglow plasma with different initial values, and the temporal evolutions of the main charged species are presented, which are dominant in reaction processes. The results show that the electron number density decays quickly. The lifetimes of electrons are shortened by about two orders with increasing ionization degree. Electrons then attach to neutral particles and produce negative ions. When the initial electron densities are in the range of 10l~ ~ 1014 cm-3, the negative ions have sufficiently high densities and long lifetimes for air purification, disinfection and sterilization. Electrons, O（2,-）, O（4,-） CO（4,-） and CO（3,-） are the dominant negative species when the initial electron density neo ≤ 1013 cm^（-3）, and only electrons and CO3 are left when neo 〉 1015 cm^（-3）. N（＋,2）, N＋ and O（＋,2） are dominant in the positive charges for any ionization degree. Other positive species, such as 0（＋,4）, N（＋,3）, NO（＋,2）, NO（＋,2）, Ar（＋,2） and H3O＋. H2O, are dominant only for a certain ionization degree and in a certain period.

关键词： ionization degree electron lifetime atmospheric plasma numerical simulation

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Construction method of quantitative evaluation model for the maturity of Korla fragrant pear

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International Journal of Agricultural and Biological Engineering 2022年第4期15卷 243-250页

作者： Shihui Yu Yurong Tang Haipeng Lan Xiaolong Li Hong Zhang Yong Zeng Hao Niu Xiaozhen Jin Yang Liu college of Mechanical and Electrical Engineering Tarim UniversityAlaer 843300XinjiangChina college of Mechanical and Electronic Engineering Shandong Agricultural UniversityTai’an271018ShandongChina zibo Agricultural Machinery Service Center Zibo 255000ShandongChina

The maturity variation laws of Korla fragrant pears were explored for a quantitative evaluation of harvest maturity to solve the reasonable matching between harvest maturity of Korla fragrant pears and market quality demands.Korla fragrant pears from different harvesting periods were chosen as the research objects.Some quality indexes were chosen as the evaluation indexes per industry standards,including hardness,soluble solid content(SSC),single-fruit weight,fruit longitudinal diameter,fruit equatorial diameter,pericarp color parameters(L*,a*,and b*),and titratable acid.Variation data of these quality indexes with accumulated temperature were collected.Scores of several quality indexes were gained through principal component analysis.A mathematical model of scores and accumulated temperatures was constructed.On this basis,a quantitative maturity model of Korla fragrant pears was constructed.Results demonstrate that SSC,single-fruit weight,fruit longitudinal diameter,fruit equatorial diameter,L*,a*,and b*are significantly and positively correlated with the accumulated temperature.Meanwhile,hardness and titratable acid showed significant negative correlations with the accumulated temperature.Relations between scores of principal components and accumulated temperature conform to the Sigmoidal model.The constructed quantitative maturity model of Korla fragrant pears can quantify the maturity of pears.Research conclusions can provide insight into the harvest periods,evaluate Korla fragrant pears’maturity,and lay a theoretical foundation for quantitative research on fruit maturity.

关键词： Korla fragrant pear quantitative evaluation maturity principal component analysis accumulated temperature

Outcome of a session of extracorporeal shock wave lithotripsy before endoscopic retrograde cholangiopancreatography for problematic and large common bile duct stones

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World Journal of Gastroenterology 2017年第27期23卷 4950-4957页

作者： Tao Tao Ming Zhang Qi-Jie Zhang Liang Li Tao Li Xiao Zhu Ming-Dong Li Gui-Hua Li Shu-Xia Sun Department of Gastroenterology Zibo Central Hospital Department of Rehabilitation Zibo Central Hospital Department of General Surgery(Breast and Thyroid Surgery) Zibo Central Hospital Department of Orthopedics(Spinal Surgery) Zibo Central Hospital Guangdong Province Key Laboratory of Medical Molecular Diagnosis Guangdong Medical College Department of Gynecology Zibo Central Hospital

AIM To compare the efficacy of a session of extracorporeal shock wave lithotripsy(ESWL) before endoscopic retrograde cholangiopancreatography(ERCP) vs ERCP only for problematic and large common bile duct(CBD) stones.METHODS Adult patients with CBD stones for whom initial ERCP was unsuccessful because of the large size of CBD stones were identified. The patients were randomized into two groups,an "ESWL + ERCP group" and an "ERCP-only" group. For ESWL + ERCP cases,ESWL was performed prior to ERCP. Clearance of the CBD,complications related to the ESWL/ERCP procedure,frequency of mechanical lithotripsy use and duration of the ERCP procedure were evaluated in both groups.RESULTS There was no significant difference in baseline characteristics between the two groups. A session of ESWL before ERCP compared with ERCP only resulted in similar outcomes in terms of successful stone removal within the first treatment session(74.2% vs 71.0%,P = 0.135),but a higher clearance rate within the second treatment session(84.4% vs 51.6%,P = 0.018) and total stone clearance(96.0% vs 86.0%,P = 0.029). Moreover,ESWL prior to ERCP not only reduced ERCP procedure time(43 ± 21 min vs 59 ± 28 min,P = 0.034) and the rate of mechanical lithotripsy use(20% vs 30%,P = 0.025),but also raised the clearance rate of extremely large stones(80.0% vs 40.0%,P = 0.016). Post-ERCP complications were similar for the two groups.CONCLUSION Based on the higher rate of successful stone removal and minimal complications,ESWL prior to ERCP appears to be a safe and effective treatment for the endoscopic removal of problematic and large CBD stones.

关键词： Extracorporeal shock wave lithotripsy Endoscopic retrograde cholangiopancreatography Common bile duct stones

The Differences between Scarlett in Gone With the Wind And Rebecca in Vanity Fair

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校园英语 2018年第18期 235-236页

作者： Gu Liulu Yangzhou technician college

Gone with the Wind is one of the most popular American novels, which is written by American female writer Margaret Mitchell.When the book was published, its sales broke many records among the publishing circles, and it is famous all over the world.The novel mainly describes the life of Scarlett who is the daughter of Tara’smaster during the American Civil War.The love triangle created between Scarlett, Ashley, and Rhett drives the narrative.Among all the roles, Scarlett, is the most successful one who is a vivid, abundant, complicated feature.Rebecca have different living conditions.While they have the same personailities.

关键词： Cleverness Ambition Rebellion Independence Selfishness and Coldness