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A stable one-point quadrature rule for three-dimensional numerical manifold method

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Science china(Technological Sciences) 2024年第5期67卷 1401-1416页

作者： ZHANG Ning ZHENG Hong YANG Liang WU WenAn yuan chi School of Civil Engineering Qinghai UniversityQinghai810016China Key Laboratory of Urban Security and Disaster Engineering Ministry of EducationBeijing University of TechnologyBeijing100124China Faculty of Engineering China University of GeoscienceWuhan430074China

We present a numerically stable one-point quadrature rule for the stiffness matrix and mass matrix of the three-dimensional numerical manifold method(3D NMM).The rule simplifies the integration over irregularly shaped manifold elements and overcomes locking issues,and it does not cause spurious modes in modal *** essential idea is to transfer the integral over a manifold element to a few moments to the element center,thereby deriving a one-point integration rule by the moments and making modifications to avoid locking *** the stiffness matrix,after the virtual work is decomposed into moments,higher-order moments are modified to overcome locking issues in nearly incompressible and bending-dominated *** the mass matrix,the consistent and lumped types are derived by *** particular,the lumped type has the clear advantage of *** proposed method is naturally suitable for 3D NMM meshes automatically generated from a regular *** tests justify the accuracy improvements and the stability of the proposed procedure.

关键词： three-dimensional numerical manifold method quadrature rule locking mass lumping

An Adaptive Many-objective Robust Optimization Model of Dynamic Reactive Power Sources for Voltage Stability Enhancement

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Journal of Modern Power Systems and Clean Energy 2023年第6期11卷 1756-1769页

作者： yuan chi Anqi Tao Xiaolong Xu Qianggang Wang Niancheng Zhou IEEE State Key Laboratory of Power Transmission Equipment and System Security and New Technology Chongqing UniversityChongqing 400044China

The deployment of dynamic reactive power sourcecan effectively improve the voltage performance after a disturbance for a power system with increasing wind power penetration level and ubiquitous induction *** improve the voltage stability of the power system,this paper proposes an adaptive many-objective robust optimization model to deal with thedeployment issue of dynamic reactive power ***,two metrics are adopted to assess the voltage stability of the system at two different stages,and one metric is proposed to assess the tie-line reactive power ***,a robustness index isdeveloped to assess the sensitivity of a solution when subjectedto operational uncertainties,using the estimation of acceptablesensitivity region(ASR)and D-vine *** objectives areoptimized simultaneously:①total equipment investment;②adaptive short-term voltage stability evaluation;③tie-line power flow evaluation;④prioritized steady-state voltage stabilityevaluation;and⑤robustness ***,an anglebased adaptive many-objective evolutionary algorithm(MaOEA)is developed with two improvements designed for the application in a practical engineering problem:①adaptive mutationrate;and②elimination procedure without a requirement for athreshold *** proposed model is verified on a modifiedNordic 74-bus system and a real-world power *** results demonstrate the effectiveness and efficiency of theproposed model.

关键词： Voltage stability reactive power planning robust many-objective optimization tie-line correlated uncertainty

Numerical simulation and experimental study on eggshell membrane separation device

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International Journal of Agricultural and Biological Engineering 2019年第2期12卷 173-183页

作者： yuan chi Yong Wang Mengfu Li Jie Ren Yujie chi College of Engineering Northeast Agricultural UniversityHarbin 150030China College of Food Science Northeast Agricultural UniversityHarbin 150030China

In order to provide theoretical guidance for separating egg membrane from eggshell by using mechanical agitation,CFD was used to explore the flow characteristics in stirred tank,using the Sliding Grid method to deal with the impeller rotational velocity zone in flow field,and using the Euler model to deal with liquid-solid two-phase *** study explored the influence of dish-shape bottom or flat-shape bottom,the clearance size between baffle and the side wall,and the axial height of impeller to bottom on suspension state of particles,solids holdup distribution,solid phase velocity and power number by *** results showed that better particles suspension effect in dish-shape tank can reduce particles accumulation at the bottom and power *** there was a small clearance size(S)between the baffle and the side wall of the stirred tank,it would reduce particles accumulation at the bottom,and reduce the power ***,too large S would decrease the suspension height of particles,not only cannot strengthen the main flow,but also lead to most fluid through clearance forming tangential flow,simulation results showed that S=6 mm was *** decreased axial height of impeller(C)to bottom,particles accumulation at the bottom was decreased,but power consumption would increase,simulation results showed that C=H/5(H is height of liquid surface)was *** to the simulation results,the structure of the stirring tank was *** the same time,the influences of stirring rotational velocity,stirring time,solid-liquid ratio and separating medium temperature on egg membrane recovery were also studied by experiment,and optimal parameter combination of factors was *** experiment results showed while the stirring time was 17.1 min,stirring rotational velocity was 350 r/min,solid-liquid ratio was 1:17 g/mL,the separating medium temperature was 32℃,the membrane recovery rate can reach above 89%.The device improves the recovery a

关键词： liquid-solid two-phase flow mechanical stirring field characteristics eggshell membrane separation

Differences in protein composition and functional properties of egg whites from four chicken varieties

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Food Bioscience 2022年第2期46卷 934-941页

作者： Ruihan Yu yuan chi Yanqiu Ma Yujie chi Lifeng Wang College of Food Science Northeast Agricultural UniversityHarbinHeilongjiang150030China College of Engineering Northeast Agricultural UniversityHarbinHeilongjiang150030China

Egg white protein(EWP)is widely used in the food industry for its technological properties,which are affected by diet-and breed-related changes in its ***,the objective of this study was to analyse the relationship between hen variety and the protein composition,functional characteristics,and physicochemical properties of egg white(EW)obtained from Black Bone(BB),Gushi(GS),Hy-Line(HY-LINE),and Harbin White(HW)*** protein composition of EW was analysed by high performance liquid chromatography(HPLC),while the secondary structure of EWP was assessed by Raman *** and GS EWs had significantly higher ovalbumin content(183.38 and 168.56μg/mL,respectfully)than HY-LINE and HW EWs(148.15 and 147.44μg/mL,respectfully)(pchildren’s growth and preterm infant *** conclusion,differences in protein composition likely led to dissimilar functional and physicochemical properties among EWs obtained from different hen varieties,which could provide a reference for food production and genetic breeding of laying hens.

关键词： Egg white protein Protein content Functional and physicochemical properties High performance liquid chromatography

Multi-stage Coordinated Robust Optimization for Soft Open Point Allocation in Active Distribution Networks with PV

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Journal of Modern Power Systems and Clean Energy 2023年第5期11卷 1553-1563页

作者： Anqi Tao Niancheng Zhou yuan chi Qianggang Wang Guangde Dong State Key Laboratory of Power Transmission Equipment and System Security and New Technology Chongqing UniversityChongqing 400044China State Grid Chongqing Electric Power Company Limited Chongqing 401123China

To optimize the placement of soft open points(SOPs)in active distribution networks(ADNs),many aspects should be considered,including the adjustment of transmission power,integration of distributed generations(DGs),coordination with conventional control methods,and maintenance of economic *** address this multi-objective planning problem,this study proposes a multi-stage coordinated robust optimization model for the SOP allocation in ADNs with photovoltaic(PV).First,two robust technical indices based on a robustness index are proposed to evaluate the operation conditions and robust optimality of the ***,the proposed coordinated allocation model aims to optimize the total cost,robust voltage offset index,robust utilization index,and voltage collapse proximity ***,the optimization methods of the multiand single-objective models are coordinated to solve the proposed multi-stage ***,the proposed model is implemented on an IEEE 33-node distribution system to verify its *** results show that the proposed index can better reveal voltage offset conditions as well as the SOP utilization,and the proposed model outperforms conventional ones in terms of robustness of placement plans and total cost.

关键词： Multi-stage coordinated optimization allocation robustness index soft open point(SOP) active distribution network

Protective effect of TMP on pancreas function of acute pancreatitis rats

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Asian Pacific Journal of Tropical Medicine 2015年第6期8卷 474-477页

作者： yuan-chi Weng Jia-Qiao Fan Department of General Surgery Rui-Jin HospitalShanghai Jiao Tong University School of Medicine First Affiliated Hospital of Dalian Medical University

Objective:To explore the protective effect and mechanism of Tetramethyl Pyrazine(TMP)on the pancreas function of acute pancreatitis ***:A total of 75 SD rats were randomly divided into three groups(A,B,C) with 25 rats in each *** A served as sham operation *** the groups B and C,AP model was prepared as by injecting taurocholic acid *** B was model *** modeling,rats were administrated by intraperitoneal injection of normal *** C was TMP treatment group,which was administrated by intraperitoneal injection of 0.6% TMP after *** rat blood specimens in each group were collected with 1 mL/100 g solution after modeling of 2,6.12 and 24 *** of amylase(AMS).blood urea nitrogen(BUN),creatinine(CR).TNF-α and IL-6 were detected,and 5 rats were *** examination was performed in he pancreatic tissue specimens of each group to observe pancreatic tissue ***:After modeling in each time ***,***-α and IL-6 in groups B and C were significantly higher than that of in group A(P<0.05).After modeling of 2 *** and CR in group B increased significantly and reached the peak value at6 *** modeling of 12 *** level of TNF-α and IL-6 were significantly lower than that of in control group,while after 24 h of modeling,serum level of ***,CR,TNF-α and IL-6 were significantly lower than that of in control group(P<0.05).The histological observation showed that pancreatic tissue in rats of group A was normal without damage *** bleeding,necrosis and serious injury were visible in pancreatic tissue of group *** rut pancreatic tissue was bleeding in group C with small pieces of necrotic *** degree of inflammatory cell infiltration was lower than group *** the degree of injury was significantly lower than group ***:TMP can significantly decrease the serum level of TNF- α and IL-6 in AP rats,inhibits inflammatory response of *** has significant

关键词： TMP Acute pancreatitis TNF-α IL-6

The effect of COVID-19 vaccines on sperm parameters: a systematic review and meta-analysis

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Asian Journal of Andrology 2023年第4期25卷 468-473页

作者： Yu-Cheng Ma Chao Cheng chi yuan Li-yuan Xiang Jun Wen Xi Jin Department of Urology Institute of Urology(Laboratory of Reconstructive Urology)West China HospitalSichuan UniversityChengdu 610000China

Published data were gathered for a meta-analysis to determine the difference in sperm parameters before and after administration of different types of coronavirus disease 2019(COVID-19)vaccines,because the reproductive toxicity of COVID-19 vaccines has not yet been evaluated in clinical trials and COVID-19 has been associated with decreases in sperm *** preferred procedures for systematic reviews and meta-analyses were followed in the conduct and reporting of this *** average sperm parameters of all sperm donors’multiple sperm donations were compared before and after receiving various COVID-19 *** volume,total sperm motility,total sperm count,morphological change,and sperm concentration were the primary outcome *** compiled and analyzed the results of six studies on total sperm motility,six studies on semen volume,six studies on sperm concentration,two studies on morphological change,and two studies on total sperm *** comparisons with patients who had and had not been vaccinated were only reported in one of the included *** different types of COVID-19 vaccine injections were compared,no discernible differences in parameters were *** to the available data,the parameters of semen are unaffected by inactivated or messenger RNA(mRNA)COVID-19 *** support these findings,additional prospectively designed research is required.

关键词： COVID-19 mRNA vaccine sperm parameters sperm quality vaccine safety

Spatiotemporal Variation of Plant Diversity Under a Unique Estuarine Wetland Gradient System in the Yellow River Delta, china

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chinese Geographical Science 2020年第2期30卷 217-232页

作者： SUN Jingkuan chi yuan FU Zhanyong LI Tian DONG Kaikai Shandong Key Laboratory of Eco-Environmental Science for Yellow River Delta Binzhou UniversityBinzhou 256603ShandongChina First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China

Multiple natural and human factors in estuarine wetlands result in complicated land surface characteristics with distinct spatial and temporal heterogeneities,thereby contributing to the difficulty in identifying spatiotemporal variations and influencing factors of plant diversity.A unique estuarine wetland gradient system(UEWGS)consisting of soil,vegetation,heat,distance,landscape,and anthropogenic gradients was established based on the ecological features of estuarine wetland through remote sensing and field investigation *** resolved the complicated land surface characteristics,covered all aspects of factors influencing plant diversity,and possessed distinct spatiotemporal *** Yellow River Delta,the largest estuarine wetland in the northern china,was selected as the study area to demonstrate UEWGS in four seasons in 2017.A total of 123 species were recorded with considerable seasonal *** australis,Suaeda salsa,and Tamarix chinensis were the dominant species,and crop species also played important *** single effect,all aspects of gradients exerted significant influences,yet only vegetation gradient possessed significant influences in all *** comprehensive effect,soil,vegetation,heat,and distance gradients showed significant gross *** content in soil gradient and net primary productivity in vegetation gradient possessed significant net influences in all seasons and can be considered as the main driving factor and indicator,respectively,of plant *** results validated the significance of UEWGS in revealing the plant diversity spatiotemporal characteristics and influencing factors,and UEWGS possessed universal applicability in the spatiotemporal analysis of plant diversity in estuarine areas.

关键词： plant diversity spatiotemporal variation single effect comprehensive effect Yellow River Delta

Multi-objective Day-ahead Polarity Switching Optimization for Voltage Unbalance in Bipolar DC Distribution Networks

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Journal of Modern Power Systems and Clean Energy 2023年第4期11卷 1212-1223页

作者： Zhongchi Huang Qianggang Wang yuan chi Jianquan Liao Yu Zhang Niancheng Zhou Chongqing University ChongqingChina Sichuan University ChengduChina State Grid Chongqing Shibei Electric Power Supply Branch ChongqingChina

Bipolar direct current(DC)distribution networks can effectively improve the connection flexibility for renewable generations and *** practice,concerns regarding the potential voltage unbalance issue of the distribution networks and the frequency of switching still *** paper proposes a day-ahead polarity switching strategy to reduce voltage unbalance by optimally switching the polarity of renewable generations and loads while minimizing the switching times simultaneously in the range of a full ***,a multi-objective optimization model is constructed to minimize the weighted sum of voltage unbalance factors and the sum of number of switching actions in the day based on the power flow ***,a two-step solution strategy is proposed to solve the optimization ***,the proposed strategy is validated using 11-node and 34-node distribution networks as case studies,and a switching and stabilizing device is designed to enable unified switching of renewable generations and *** results demonstrate that the proposed strategy can effectively reduce the switching times without affecting the improvement of voltage balance.

关键词： Bipolar direct current(DC)distribution network multi-objective optimization renewable generation voltage unbalance