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Research on new type of fast-opening mechanism in steam turbine regulating system and optimization of operation tactic

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第5期9卷 633-639页

作者： Xiao-xiao LI xuan-yin WANG Fu-shang LI The State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China Shandong Electrical Power Institute Jinan 250002 China

With the analysis on regulating system in 200 MW steam turbine, the necessity of appending the fast-opening function to the original system is set forth and a new type of fast-opening mechanism is devised. The mathematical model of system is built up. With the use of AMESIM software, the displacement curve of the piston, the force curve of the cartridge valve spool, the pressure curve and the flux curve in the regulation process are obtained based on simulation. The performances of three fast-opening systems composed of cartridge valves with different diameters are compared. Based on the analysis on factors that affect the execution time of fast-opening, the dead zone of the fast-opening system is put forward. To overcome the defect, dif- ferent operation modes are adopted for different zones. The result shows that with the increase of the valve diameter, the regulating time in the dead zone significantly exceeds the fast-opening time in the whole journey. Accordingly, the optimization operation tactic in the dead zone and the qualification conditions are brought forward. The fast-opening system composed of 32 mm cartridge valves is taken as an example with use of the tactic. The simulation result shows that the maximum regulating time is shortened by 509 ms.

关键词： Steam turbine Fast-opening Regulating system AMESIM

Research on the operating characteristics of parallel 4-DOF electric platform with 4TPS-PS structure

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第11期8卷 1800-1807页

作者： CHENG Jia WANG xuan-yin FU Xiao-jie LI Qiang The State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

The 4TPS-PS parallel platform designed for a stabilization and automatic tracking system is a novel lower-mobility parallel mechanism. In the first part of this paper, the structure of the platform is described and the kinematics model is built. The workspace of the platform is defined as the full reachable rotation workspace when the Z coordinate dimension of the upper plate varies continuously. A fast searching method of the full reachable workspace is presented, after which the inverse kinematics of the platform is deduced. The forward and inverse solutions of the speed and force of the platform are deduced. According to the characteristic of the 4TPS-PS platform’s structure, a fast searching algorithm of the maximum generalized speed and maximum generalized force output by the upper plate is put forward based on the forward and inverse solutions of the platform’s speed and force. The 4TPS-PS platform prototype built by the State Key Laboratory of Fluid Power Transmission and Control of China is taken as the research subject. The full reachable rotation workspace of the prototype is computed out and analyzed. The curves of maximum generalized speed and maximum generalized force of the prototype are computed out and plotted. Finally, the com- puting and analyzing results of the operating characteristics are confirmed through the experiment.

关键词： Parallel mechanism 4-DOF Workspace Generalized speed Generalized force

Design and Kinematic Analysis of a Novel Humanoid Robot Eye Using Pneumatic Artificial Muscles

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Journal of Bionic Engineering 2008年第3期5卷 264-270页

作者： xuan-yin Wang Yang Zhang Xiao-jie Fu Gui-shan Xiang State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 P. R. China

This paper proposed a novel humanoid robot eye, which is driven by six Pneumatic Artificial Muscles （PAMs） and rotates with 3 Degree of Freedom （DOF）. The design of the mechanism and motion type of the robot eye are inspired by that of human eyes. The model of humanoid robot eye is established as a parallel mechanism, and the inverse-kinematic problem of this flexible tendons driving parallel system is solved by the analytical geometry method. As an extension, the simulation result for saccadic movement is presented under three conditions. The design and kinematic analysis of the prototype could be a sig- nificant step towards the goal of building an autonomous humanoid robot eye with the movement and especially the visual functions similar to that of human.

关键词： bionic robotics bio-inspiration humanoid robot eye air muscle inverse-kinematic

Clinical potentials of ginseng polysaccharide for treating gestational diabetes mellitus

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World Journal of Clinical Cases 2021年第19期9卷 4959-4968页

作者： xuan-yin Zhao Fang Zhang Wei Pan Yi-Fang Yang Xiao-Ya Jiang First Affiliated Hospital Guizhou University of Traditional Chinese MedicineGuiyang 550002Guizhou ProvinceChina Maternal and Child Health Hospital of Guiyang Guiyang 550002Guizhou ProvinceChina

Gestational diabetes mellitus(GDM)is the most common glucose metabolism complication or cause of potential impaired glucose tolerance that can occur either before or during pregnancy and *** prevalence of GDM and its related complications in young women is increasing,and this condition may cause serious outcomes and health hazards to the ***,traditional oral hypoglycaemic drugs have potential safety hazards;therefore,it is urgent to develop new,safe,effective,and easily administered agents and *** polysaccharide(GPS),which is isolated from Panax(P.)ginseng ***,exhibits notably promising biological activities and effects;specifically,it has been shown to lower blood glucose with mild,safe,and nontoxic characteristics,and it can also improve human bodily ***,we hypothesise that GPS might be used as an additional therapy and candidate agent for treating *** review innovatively summarizes the available reports and evidence from basic studies to analyze the potential for and feasibility of using GPS as a new therapeutic agent for treating ***,for the first time,this review provides a rationale for the use of *** summarized results show that GPS may be developed as a novel antidiabetic drug and a remedy for use in preventing and treating GDM,with great application prospects.

关键词： Ginseng polysaccharide Gestational diabetes mellitus Biological activities Anti-diabetes Review

Studies of ultrasound disintegration of residual sludge and its energy consumption in water treatment of petrochemical plant

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Frontiers of Chemical Science and Engineering 2007年第4期1卷 395-398页

作者： SHEN Jinfeng yin xuan GU Heping Lü Xiaoping Institute of Sonochemical Engineering Nanjing University of TechnologyNanjing 210009China

To investigate the influence of ultrasound pretreatment on sludge anaerobic digestion,the ultrasound disintegration of residual sludge in water treatment of petrochemical plant was studied,and the mechanisms of ultrasound and medium were *** results indicate that ultrasound cavitation induces the rise of sludge temperature,which improves ultrasound disintegra-tion on sludge.U1trasound pretreatment can advance observ-ably the quantity of chemical oxygen demand in sludge supernatant fluid(SCOD),which increases with ultrasound intensity and sonication *** degree of ultrasound disintegration increases with the specific energy *** the specific energy input is l0000 kJ/kg of total dry solids,the degree of ultrasonic sludge disintegration reaches 40%.

关键词： residual sludge chemical oxygen demand ultrasonic cavitation specific energy consumption

IP Lyn:A Totally Eclipsing Contact Binary with an Extremely Low Mass Ratio

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Research in Astronomy and Astrophysics 2023年第8期23卷 206-219页

作者： Zi-xuan yin Zi-Bin Meng Pei-Ru Wu Xu-Dong Zhang Yun-Xia Yu Ke Hu Fu-Yuan Xiang Key Laboratory of Star and Interstellar Medium Xiangtan UniversityXiangtan 411105China School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550025China Department of Physics Xiangtan UniversityXiangtan 411105China

We present the first photometric and orbital period investigations for a neglected totally eclipsing contact binary IP *** photometric solutions derived from both ground-based and several surveys'observations suggest that it is a shallow contact binary with an extremely low mass ratio of *** weak asymmetry observed in our multiple band light curves can be interpreted as a result of an active cool spot on the *** absolute physical parameters were determined with the Gaia-distance-based method and checked by an empirical *** the eclipse timings collected from the literature and those derived from our and variable surveys'observations,we find that IP Lyn has been undergoing a secular orbital period increase for the past two decades,implying a mass transfer from the less massive secondary to the *** comparing the current parameters with the critical instability ones,we infer that IP Lyn is currently stable in spite of its relatively low mass ratio and orbital angular ***,from a catalog of 117 extremely low mass ratio contact binaries,we find that their orbital angular momenta are significantly lower than those of the contact binaries with a relatively high mass ratio,suggesting they should be at the late evolutionary stage of a contact binary.

关键词： (stars")binaries(including multiple) close-(stars:)binaries eclipsing-stars evolution-stars individual(IP Lyn)

Investigating Müller glia reprogramming in mice: a retrospective of the last decade, and a look to the future

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Neural Regeneration Research 2025年第4期20卷 946-959页

作者： Zhiyuan yin Jiahui Kang xuan Cheng Hui Gao Shujia Huo Haiwei Xu Key Lab of Visual Damage and Regeneration&Restoration of Chongqing Southwest Eye HospitalSouthwest HospitalThird Military Medical University(Army Medical University)ChongqingChina

Müller glia,as prominent glial cells within the retina,plays a significant role in maintaining retinal homeostasis in both healthy and diseased *** lower vertebrates like zebrafish,these cells assume responsibility for spontaneous retinal regeneration,wherein endogenous Müller glia undergo proliferation,transform into Müller glia-derived progenitor cells,and subsequently regenerate the entire retina with restored ***,Müller glia in the mouse and human retina exhibit limited neural reprogramming.Müller glia reprogramming is thus a promising strategy for treating neurodegenerative ocular disorders.Müller glia reprogramming in mice has been accomplished with remarkable success,through various *** in molecular,genetic,epigenetic,morphological,and physiological evaluations have made it easier to document and investigate the Müller glia programming process in ***,there remain issues that hinder improving reprogramming efficiency and ***,understanding the reprogramming mechanism is crucial toward exploring factors that will improve Müller glia reprogramming efficiency,and for developing novel Müller glia reprogramming *** review describes recent progress in relatively successful Müller glia reprogramming *** also provides a basis for developing new Müller glia reprogramming strategies in mice,including epigenetic remodeling,metabolic modulation,immune regulation,chemical small-molecules regulation,extracellular matrix remodeling,and cell-cell fusion,to achieve Müller glia reprogramming in mice.

关键词： cell fusion chemical small-molecules epigenetic extracellular matrix immune metabolic mice Müller glia neurodegenerative diseases reprogramming retina regeneration

Comparative effectiveness of several adjuvant therapies after hepatectomy for hepatocellular carcinoma patients with microvascular invasion

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 554-570页

作者： yin-xuan Pei Chen-Guang Su Zheng Liao Wei-Wei Li Zi-Xiang Wang Jin-Long Liu Department of Hepatobiliary Surgery The Affiliated Hospital of Chengde Medical UniversityChengde 067000Hebei ProvinceChina

BACKGROUND For resectable hepatocellular carcinoma(HCC),radical hepatectomy is commonly used as a curative ***,postoperative recurrence significantly diminishes the overall survival(OS)of HCC patients,especially with microva-scular invasion(MVI)as an independent high-risk factor for *** some studies suggest that postoperative adjuvant therapy may decrease the risk of recurrence following liver resection in HCC patients,the specific role of adju-vant therapies in those with MVI remains *** To conduct a network meta-analysis(NMA)to evaluate the efficacy of various adjuvant therapies and determine the optimal adjuvant *** A systematic literature search was conducted on PubMed,EMBASE,and Web of Science until April 6,*** comparing different adjuvant therapies or comparing adjuvant therapy with hepatectomy alone were *** ratios(HRs)with 95%confidence intervals were used to combine data on recurrence free survival and OS in both pairwise meta-analyses and *** Fourteen eligible trials(2268 patients)reporting five different therapies were *** terms of reducing the risk of recurrence,radiotherapy(RT)[HR=0.34(0.23,0.5);surface under the cumulative ranking curve(SUCRA)=97.7%]was found to be the most effective adjuvant therapy,followed by hepatic artery infusion chemotherapy[HR=0.52(0.35,0.76);SUCRA=65.1%].Regarding OS improvement,RT[HR:0.35(0.2,0.61);SUCRA=93.1%]demonstrated the highest effectiveness,followed by sorafenib[HR=0.48(0.32,0.69);SUCRA=70.9%].INTRODUCTION Hepatocellular carcinoma(HCC)is the sixth most common malignant tumor in the world and ranks third in terms of worldwide malignant tumor mortality rates in 2020[1].Curative treatments for HCC include ablation,radical hepatectomy,and liver ***,ablation is suitable only for early-stage HCC patients,who represent a small percentage of the overall HCC *** liver transplantation serves as the optimal tre

关键词： Hepatocellular carcinoma Adjuvant therapy Network meta-analysis Transarterial chemoembolization Hepatic artery infusion chemotherapy Radiotherapy Sorafenib

Effects of the pestle needle therapy,a type of acupoint stimulation,on post-hemorrhoidectomy pain:A randomized controlled trial

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Journal of Integrative Medicine 2020年第6期18卷 492-498页

作者： Xian Wang xuan yin Xiu-tian Guo Yan Wang Wen-qi Jin Ai-jun Mao Lixing Lao Zhang-jin Zhang Jie Zhang Shi-fen Xu Department of Nursing Shanghai Municipal Hospital of Traditional Chinese MedicineShanghai University of Traditional Chinese MedicineShanghai 200071China Department of Acupuncture and Moxibustion Shanghai Municipal Hospital of Traditional Chinese MedicineShanghai University of Traditional Chinese MedicineShanghai 200071China Department of Proctology Shanghai Municipal Hospital of Traditional Chinese MedicineShanghai University of Traditional Chinese MedicineShanghai 200071China School of Chinese Medicine Li Ka Shing Faculty of MedicineThe University of Hong KongHong KongChina Virginia University of Integrative Medicine FairfaxVA 22031USA

Background:Hemorrhoids are one of the most common conditions that lead to surgery,and until now surgical hemorrhoidectomy has been the major effective ***-operative pain from hemorrhoidectomy has been experienced by thousands of patients and remains a major inconvenience of the ***:This study evaluates the clinical efficacy of the pestle needle therapy,an acupoint stimulation method,for relief of post-hemorrhoidectomy ***,setting,participants and interventions:This was a single-center,patient-assessor-blinded and randomized controlled trial with 154 patients receiving Milligan hemorrhoidectomy *** patients were randomly assigned to either a treatment group or a control group at a ratio of 1:*** treatment group received the pestle needle therapy,with manual stimulation at Yaoshu(DU2),Mingmen(DU4),Changqiang(DU1),Chengshan(BL57),Erbai(EX-UE2)and the perianal points(1,3,5,7,9,and 11 o’clock around the lesion);while the control group received a sham treatment with very light *** sessions of treatment were performed at 30 min,4 h and 12 h after the surgery,and each lasted for 15 *** outcome measures:The primary outcome was post-operative pain measured with the visual analogue scale(VAS)at 12 h after *** secondary outcomes included the VAS scores measured at0.5,2,4,6,8,24 and 48 h after surgery,the analgesic dose,the time and the VAS score of the patients’first defecation after surgery,as well as the Hamilton Rating Scale for Anxiety(HAMA)evaluated before ***:The mean pain score of the treatment group was significantly lower than that of the control group(3.10±1.27 vs 4.82±1.29;P<0.001)at 12 h after *** with the control group,patients in the treatment group needed a smaller dose of analgesic within the first 24 hours after surgery(P=0.002);and their HAMA scores before discharge were lower(4.07±2.40 vs 5.10±2.45,P=0.009).Compared to the treatment group,patients in the contr

关键词： Pestle needle Acupoint stimulation Hemorrhoidectomy Post-operative pain Randomized controlled trial