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Disturbances rejection optimization based on improved two-degree-of-freedom LADRC for permanent magnet synchronous motor systems

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Defence Technology（防务技术） 2024年第3期33卷 518-531页

作者： Chenggang Wang Jianhu Yan Wenlong Li Liang Shan le Sun School of Automation Nanjing University of Science and TechnologyNanjing 210094China

Permanent magnet synchronous motor(PMSM)speed control systems with conventional linear active disturbance rejection control(CLADRC)strategy encounter issues regarding the coupling between dynamic response and disturbance suppression and have poor performance in suppressing complex nonlinear *** order to address these issues,this paper proposes an improved two-degree-of-freedom LADRC(TDOF-LADRC)strategy,which can enhance the disturbance rejection performance of the system while decoupling entirely the system's dynamic and anti-disturbance performance to boost the system robustness and simplify controller parameter *** models that consider total disturbances are developed to design the TDOF-LADRC speed controller ***,to evaluate the control performance of the TDOF-LADRC strategy,its stability is proven,and the influence of each controller parameter on the system control performance is *** on it,a comparison is made between the disturbance observation ability and anti-disturbance performance of TDOF-LADRC and CLADRC to prove the superiority of TDOF-LADRC in rejecting ***,experiments are performed on a 750 W PMSM experimental platform,and the results demonstrate that the proposed TDOF-LADRC exhibits the properties of two degrees of freedom and improves the disturbance rejection performance of the PMSM system.

关键词： Permanent magnet synchronous motor(PMSM) Active disturbance rejection control(ADRC) Disturbance observer Two-degree-of-freedom control Anti-disturbance

A rare case of hepatic vein-portal vein fistula with hepatolithiasis presenting as cholangiocarcinoma

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 538-540页

作者： Wei Li Wen Lin le Xiao General Surgery Center The General Hospital of Western Theater CommandChengdu 610083China

To the Editor: We sincerely applaud the work by Tang et al., in which they described caudate lobe-sparing subtotal hepatectomy as treatment for intrahepatic arterioportal fistulas [ 1 ]. Compared to intrahepatic arterioportal fistulas, portal vein-hepatic vein fistulas are rarely reported. Patients typically lack clinical symptoms such as hyperammonemia, cholestatic jaundice, and hypoglycemia, unless the shunt becomes relatively large [ 2, 3 ]. Herein, we describe partial hepatectomy as a treatment for cases of left portal vein-middle hepatic vein fistulas.

关键词： hepatic clinical

Mineralogical properties and co-sintering characteristics of fluxed iron ore with magnetite concentrates

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Journal of Iron and Steel Research International 2024年第2期31卷 318-328页

作者： le-le Niu Zheng-jian Liu Jian-liang Zhang Yao-zu Wang Zhen-xing Yang Si-da Li Chang-dong Shan Ben Feng School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Institute of Artificial Intelligence University of Science and Technology BeijingBeijing100083China Xinxing Casting Pipe Xinjiang Co. Bayingol841300XinjiangChina

To investigate the feasibility of co-sintering of fluxed iron ore with magnetite concentrates, the mineralogical properties of a novel fluxed iron ore were studied using particle size analysis, microscopic morphology characterization, and X-ray diffraction Rietveld analysis. Following that, the experiments for granulation performance and basic sintering characteristics were designed under seven different fluxed iron ore ratios, and the integrated ranking of different fluxed iron ore ratios was determined using gray relation analysis. Finally, the results of the industrial trails were combined with the feasibility analysis. Test and experimental results show that the fraction of the fluxed iron ore particles larger than 0.5 mm can account for more than 48%, and the particles have two morphologies: spherical-rough and flaky-smooth. Ca elements are found in the form of calcite (CaCO3) and dolomite (CaMg(CO3)2). The average particle size of granules and powder removal rate can be improved from 2.50 to 3.16 mm and 39.60% to 24.20%, respectively, with the increase in the fluxed iron ore ratio. Furthermore, the fluxed iron ore can improve assimilability and liquid fluidity of magnetite concentrates. In terms of overall granulation performance and sintering characteristics, the fluxed iron ore ratios are graded from best to worst as follows: 12%, 15%, 9%, 18%, 21%, 6% and 3%. The industrial trails show that when the fluxed iron ore ratio is increased, the beneficial effect of the superior sintering characteristics of the fluxed iron ore itself is ideally balanced with the negative effect of the lower amount of additional CaO at 12% ratio, and thus, it is feasible to bring the fluxed iron ore into production at a level of roughly 12%.

关键词： Fluxed iron ore Magnetite concentrate Granulation performance Sintering characteristics Gray relation analysis

Understanding the Activity Performance of Comets 38P/Stephan-Oterma,64P/Swift-Gehrels and C/2017 M4(ATLAS)through Broadband Photometric Observations

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Research in Astronomy and Astrophysics 2024年第8期24卷 147-156页

作者： Xuan Zhang Jin-Zhong Liu le-Tian Wang Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China

In this work,we report observations of three comets:38P/Stephan-Oterma,64P/Swift-Gehrels,and C/2017 M4(ATLAS),conducted with the Nanshan one-meter wide-field telescope in 2018 August and November,and *** extracted morphological features through image enhancement techniques and calculated the dust activity parameter,Afρ,along with dust mass loss rates and coma color indices using broadband photometric *** morphological analysis uncovered a spectrum of dust characteristics among the observed comets,ranging from a significant twisted structure in comet 38P/Stephan-Oterma’s coma to the regular coma envelope surrounding comet 64P/*** Afρvalues varied between 148.8±0.3 cm for 64P/Swift-Gehrels and1118.5±6.2 cm for C/2017 M4(ATLAS)(measured within a reference aperture radius ofρ=6″),indicating a range from moderate to high activity *** mass loss rates were estimated from 328.1 kg s^(-1)for comet 64P/Swift-Gehrels to 1395.5 kg s^(-1)for comet C/2017 M4(ATLAS).The color indices of comets 38P/Stephan-Oterma and C/2017 M4(ATLAS)closely resemble the average colors of active short-period comets and active longperiod comets,*** contrast,64P/Swift-Gehrels exhibits a significantly bluer hue than typical Jupiter family comets.

关键词： comets general-comets individual(38P/Stephan-Oterma,64P/Swift-Gehrels,C/2017 M4(ATLAS))-techniques photometric

leader-follower Optimal Selection Method for Distributed Control System in Active Distribution Networks

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 314-323页

作者： Jian le Liangang Zhao Cao Wang Qian Zhou Yang Wang School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072China

Aiming at the shortcomings of a traditional centralized control in an active distribution network(AND),this paper proposes a leader-follower distributed group cooperative control strategy to realize multiple operation and control tasks for an *** distributed information exchange protocols of the distributed generation(DG)group devoted to node voltage regulation or exchange power control are developed using a DG power utilization ratio as the consensus *** these bases,this study further investigates the leader optimal selection method for a DG group to improve the response speed of the distributed control ***,a single or multiple leader selection model is established to minimize the constraints of the one-step convergence factor and the number of leaders to improve the response speed of the distributed control *** simulation results of the IEEE 33 bus standard test system show the effectiveness of the proposed distributed control *** addition,the response speed of a DG control group can be improved effectively when the single or multiple leaders are selected optimally.

关键词： Active distribution1network consensus algorithm leader-follower system mixed-integer semidefinite programming optimal distributed control

Building a More Sustainable Chinese Loess Plateau

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Journal of Earth Science 2024年第1期35卷 283-287页

作者： Peiyue Li Xiaomei Kou Yong Wang le Niu School of Water and Environment Chang'an UniversityXi'an 710054China Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education Chang'an UniversityXi'an 710054China Key Laboratory of Eco-Hydrology and Water Security in Arid and Semi-Arid Regions of the Ministry of Water Resources Chang'an UniversityXi'an 710054China PowerChina Northwest Engineering Corporation Limited Xi'an 710065China PowerChina Sinohydro Bureau 3 Co. LTD.Xi'an 710024China

The Chinese Loess Plateau,a region of remarkable ecological and economic value,grapples with significant water management challenges due to its distinctive geology and *** perspective offers a short review of the eco-environmental protection measures undertaken in the Loess Plateau,underscoring the transformative impacts of initiatives such as the“Grain for Green”***,it also highlights the enduring challenges,including land degradation,water resources issues,socio-economic inequities,and the implications of climate ***,water management emerges as a pivotal issue with far-reaching repercussions for soil conservation,biodiversity,and human *** paper concludes by proposing future actions,emphasizing the necessity for policy modifications,novel initiatives,and research to tackle these challenges and foster sustainable development in the Loess *** insights gained from this region could offer invaluable lessons for other regions confronted with similar challenges,thereby contributing to global efforts to mitigate desertification and champion sustainable development.

关键词： Loess Plateau eco-environmental protection water management sustainable development climate change

Exponentially Bounded C-semigroup and the Cauchy Initial Value Problems in Complete Random Normed Modules

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2195-2212页

作者： Son TA CONG Thang Dang HUNG Oanh le THI Department of Mathematics University of ScienceVietnam National University 334 Nguyen TraiThanh XuanHanoiVietnam Faculty of Natural Sciences Hong Duc University565 Quang TrungDong VeThanh HoaVietnam

In this paper,the notion of C-semigroup of continuous module homomorphisms on a complete random normal(RN)module is introduced and *** existence and uniqueness of solution to the Cauchy problem with respect to exponen... 详细信息

关键词： C-semigroup Cauchy problem random normed modules L^(0)-Lipschitz

Retrospective Study Immune function status of postoperative patients with colon cancer for predicting liver metastasis

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 463-470页

作者： le Xiong Fang-Chen Liu Department of Clinical Laboratory Xiangyang No.1 People’s HospitalHubei University of MedicineXiangyang 441000Hubei ProvinceChina Department of Blood Transfusion Xiangyang No.1 People’s HospitalHubei University of MedicineXiangyang 441000Hubei ProvinceChina

BACKGROUND Colon cancer(CC)has a high incidence *** resection is the main treatment method for CC;however,liver metastasis(LM)often occurs *** liver contains both innate and adaptive immune cells that monitor and remove abnormal cells and *** LM,tumor cells secrete cytokines and exosomes to adjust the immune microenvironment of the liver,thus forming an inhibitory immune microenvironment for colonization by circulating tumor *** indicates that the immune state of patients with CC plays a crucial role in the occurrence and progression of *** To observe and analyze the relationship between immune status and expression of tumor factors in patients with LM of CC,and to provide a scientific interven-tion method for promoting the patient *** A retrospective analysis was *** baseline data of 100 patients with CC and 100 patients with CC who suffered from postoperative LM and were admitted to our hospital from May 2021 to May 2023 were included in the non-occurrence and occurrence groups,*** immune status of the pa-tients and the expression of tumor factor-related indicators in the two groups were compared,and the predictive value of the indicators for postoperative LM in patients with CC was *** Compared with the non-occurrence group,the expression of serum carcinoem-bryonic antigen(CEA),CA19-9,CA242,CA72-4 and CA50 in patients in the occurrence group were significantly higher,while the expression of CD3+,CD4+,CD8+,natural killer(NK)and CD4+/CD25 in patients in the occurrence group were significantly lower(P0.05).Multivariate logistic regression model analysis revealed that the expressions of CEA,CA19-9,CA242,CA72-4,CA50,CD3+,CD4+,CD8+,NK,and CD4+/CD25 were associated with the LM in patients with *** expressions of serum CEA,CA19-9,CA242,CA72-4 and CA50,and low expressions of CD3+,CD4+,CD8+,

关键词： Colon cancer Liver metastases Immune status Tumor factors Predicted value

Re-examination of statistical relationships between dietary fats and other risk factors,and cardiovascular disease,based on two crucial datasets

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Quantitative Biology 2024年第1期12卷 117-127页

作者： Jiarui Ou le Zhang Xiaoli Ru College of Computer Science Sichuan UniversityChengduChina Department of Gynecology and Obstetrics Beijing Chao-Yang HospitalCapital Medical UniversityBeijingChina

Cardiovascular disease(CVD)is the major cause of death in many regions around the world,and several of its risk factors might be linked to *** improve public health and the understanding of this topic,we look at the recent Minnesota Coronary Experiment(MCE)analysis that used t-test and Cox model to evaluate CVD ***,these parametric methods might suffer from three problems:small sample size,right-censored bias,and lack of long-term *** overcome the first of these challenges,we utilize a nonparametric permutation test to examine the relationship between dietary fats and serum total *** address the second problem,we use a resampling-based rank test to examine whether the serum total cholesterol level affects CVD *** the third issue,we use some extra-Framingham Heart Study(FHS)data with an A/B test to look for meta-relationship between diets,risk factors,and CVD *** show that,firstly,the link between low saturated fat diets and reduction in serum total cholesterol is ***,reducing serum total cholesterol does not robustly have an impact on CVD hazards in the diet ***,the A/B test result suggests a more complicated relationship regarding abnormal diastolic blood pressure ranges caused by diets and how these might affect the associative link between the cholesterol level and heart disease *** study not only helps us to deeply analyze the MCE data but also,in combination with the long-term FHS data,reveals possible complex relationships behind diets,risk factors,and heart disease.

关键词： A/B test bioinformatics cardiovascular disease nonparametric statistics