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Fuzzy Set-Membership Filtering for Discrete-Time Nonlinear Systems

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IEEE/CAA Journal of Automatica Sinica 2022年第6期9卷 1026-1036页

作者： Jingyang Mao xiangyu meng Derui Ding Department of Control Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China Division of Electrical and Computer Engineering Louisiana State UniversityBaton RougeLA70803 USA IEEE School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourneVIC 3122Australia

In this article,the problem of state estimation is addressed for discrete-time nonlinear systems subject to additive unknown-but-bounded noises by using fuzzy set-membership ***,an improved T-S fuzzy model is introduced to achieve highly accurate approximation via an affine model under each fuzzy ***,compared to traditional prediction-based ones,two types of fuzzy set-membership filters are proposed to effectively improve filtering performance,where the structure of both filters consists of two parts:prediction and *** the locally Lipschitz continuous condition of membership functions,unknown membership values in the estimation error system can be treated as multiplicative noises with respect to the estimation ***-time recursive algorithms are given to find the minimal ellipsoid containing the true ***,the proposed optimization approaches are validated via numerical simulations of a one-dimensional and a three-dimensional discrete-time nonlinear systems.

关键词： Affine model membership functions set-membership filtering stability Takagi-Sugeno fuzzy modeling

A survey on recent progress in control of swarm systems

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Science China(Information Sciences) 2017年第7期60卷 5-28页

作者： Bing ZHU Lihua XIE Duo HAN xiangyu meng Rodney TEO School of Electrical and Electronic Engineering Nanyang Technological University The Seventh Research Division Beihang University Division of Systems Engineering Boston University Temasek Lab National University of Singapore

It has been witnessed that swarm systems are superior to individual agents in performing complicated tasks. In recent years, new results in some branches of control for swarm systems have developed and investigated with respect to various objectives and scenarios. This survey is to take a glimpse into some newly developed control techniques for swarm systems, especially those presented after 2013. The covered topics include some up-to-date progress in the areas of consensus, formation, flocking, containment, optimal coverage/mission planning, and sensor networks. Contributions and connections of the mentioned references are discussed *** on the new results in control of swarm systems, some possible new future research topics are suggested.

关键词： formation swarm systems consensus containment flocking sensor networks

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气吸式油莎豆精量播种机排种器设计和试验

吉林农业大学学报 2025年第1期47卷 185-190页

作者：赵清来陈晓明许顺孟祥宇刘海波吉林农业大学工程技术学院吉林省油莎豆农业科技有限公司

针对油莎豆种球几何性状不规则、充种流动性差等问题，以及我国油莎豆的播种机械还处在研发阶段的现状，设计了油莎豆精量播种机排种器并进行试验。首先，测量油莎豆平均质量、几何尺寸、摩擦系数等物理特性；然后，对排种盘吸种孔对油... 详细信息

针对油莎豆种球几何性状不规则、充种流动性差等问题，以及我国油莎豆的播种机械还处在研发阶段的现状，设计了油莎豆精量播种机排种器并进行试验。首先，测量油莎豆平均质量、几何尺寸、摩擦系数等物理特性；然后，对排种盘吸种孔对油莎豆的吸附力和排种盘结构进行设计，确定油莎豆种球在排种过程中的吸附力及临界条件，具体探讨了排种孔尺寸、排种盘直径、负压值及风机功率计算的影响因素和计算方法；之后，对排种器的性能进行了台架和田间试验。台架试验结果表明：在不同吸种孔直径和作业速度条件下，排种器的漏播率≤2.4%，重播率≤2.8%，穴距合格指数≥91.2%；田间试验表明，排种器漏播率≤4.2%，重播率≤3.1%，穴距合格指数≥90.9%，满足标准要求，可以在油莎豆种植机械中推广应用。

关键词：油莎豆播种机排种器田间试验

Numerical and experimental research on axial injection end-burning hybrid rocket motors with polyethylene fuel

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Chinese Journal of Aeronautics 2024年第8期37卷 91-105页

作者： xiangyu meng Hui TIAN Lingfei HE Jingfei GAO Xiaoting NIU Guobiao CAI School of Astronautics Beihang UniversityBeijing 100191China Key Laboratory of Spacecraft Design Optimization&Dynamic Simulation Technologies Ministry of EducationBeijing 100816China

This study investigates the end-burning hybrid rocket motors with polyethylene fuel by the numerical simulation and *** on computational fluid dynamics,a numerical model is *** model is validated by two firing tests in this hybrid rocket motor,which uses oxygen and polyethylene as *** results show that the numerical and experimental data are in good agreement,and the error of the chamber pressure is less than 2.63%.Based on the simulation mode,the blowoff limit of the end-burning hybrid rocket motors is *** the nozzle throat diameter and the inner diameter of grain are large,it is more difficult for the hybrid rocket motor to achieve end-burning mode,i.e.,the flame spreading is prevented in the narrow *** main reason is that when the nozzle throat and the grain port are large,chamber pressure and oxidizer flow velocity are ***,the friction velocity considering the pressure and flow velocity is *** critical friction velocity is about 4.054–4.890 m/s in the hybrid rocket *** the friction velocity exceeds the critical friction velocity,the combustion mode in hybrid rocket motors changes from the flame spreading mode to the end-burning ***,the regression rate formula is obtained by fitting,which shows that the regression rate has a good correlation with combustion chamber *** critical friction velocity and regression rate formula can provide an important reference for end-burning hybrid rocket motors.

关键词： Hybrid rocket motor End burning Blowoff limit Flame propagation Regression rate

A comprehensive fluid-solid coupling dynamic simulation for spatiotemporal distribution of regression rate in hybrid rocket motors

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Chinese Journal of Aeronautics 2024年第9期37卷 100-112页

作者： Tianfang WEI Guobiao CAI Hui TIAN xiangyu meng Xianzhu JIANG Xiaoming GU School of Astronautics Beihang UniversityBeijing 100191China Key Laboratory of Spacecraft Design Optimization&Dynamic Simulation Technologies Ministry of Education Beijing 100191China

The spatiotemporal distribution characteristics of the regression rate are crucial aspects of the research on Hybrid Rocket Motor(HRM). This study presents a pioneering effort in achieving a comprehensive numerical simulation of fluid dynamics and heat transfer in both the fluid and solid regions throughout the entire operation of an HRM. To accomplish this, a dynamic grid technique that incorporates fluid–solid coupling is utilized. To validate the precision of the numerical simulations, a firing test is conducted, with embedded thermocouple probes being used to measure the inner temperature of the fuel grain. The temperature variations in the solid fuel obtained from both experiment and simulations show good agreement. The maximum combustion temperature and average thrust obtained from the simulations are found to deviate from the experimental results by only 3.3% and 2.4%, respectively. Thus, it can be demonstrated that transient numerical simulations accurately capture the fluid–solid coupling characteristics and transient regression rate. The dynamic simulation results of inner flow field and solid region throughout the entire working stage reveal that the presence of vortices enhances the blending of combustion gases and improves the regression rate at both the front and rear ends of the fuel grain. In addition, oscillations of the regression rate obtained in the simulation can also be well corresponded with the corrugated surface observed in the experiment. Furthermore, the zero-dimension regression rate formula and the formula describing the axial location dependence of the regression rate are fitted from the simulation results, with the corresponding coefficients of determination(R^(2)) of 0.9765 and 0.9298, *** research serves as a reference for predicting the performance of HRM with gas oxygen and polyethylene, and presents a credible way for investigating the spatiotemporal distribution of the regression rate.

关键词： Hybrid Rocket Motor(HRM) Transient numerical simulation Fluid-solid couplingheat transfer Spatiotemporal distribution of regression rate Dynamic grid

Sex bias in FGFR3 somatic mutations in bladder cancer

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Oncology and Translational Medicine 2024年第5期10卷 252-256页

作者： xiangyu meng Qiaoli Wang Health Science Center HubeiMinzuUniversityEnshiChina Department of Medical Oncology Dana-Farber Cancer Institute and Harvard Medical SchoolBostonMA

Background:Strong sex disparities have been observed among patients with bladder cancer(BCa).FGFR3 is one of the most frequently mutated genes in bladder cancer,and there are inconsistencies in its frequency in male and female ***:Here,we conducted a meta-analysis comparing the FGFR3 somatic mutation frequency in men and women among 7351 patients with BCa from 18 ***:We showed that female patients had a 1.32 times higher risk of having FGFR3 somatic mutations than *** difference was attributed to mutations occurring at the 2 most frequently mutated sites,S249 and ***,nonsense mutations were more likely to be found in women,whereas indel/frameshift mutations were almost exclusively found in men;however,no difference was noted for missense ***:A female sex bias in FGFR3 somatic mutationswas observed in ***-powered individual participant data analyses addressing the possible confounding effects of other factors(eg,age,ethnicity,smoking status,muscle invasiveness,and molecular subtype),as well as analyses integrating omics and functional investigations,are warranted to further validate and explain the mechanisms of the current findings.

关键词： bladder cancer FGFR3 sex bias somatic mutations

A Novel Routing Method for Social Delay-Tolerant Networks

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Tsinghua Science and Technology 2019年第1期24卷 44-51页

作者： xiangyu meng Gaochao Xu Tingting Guo Yongjian Yang Wenxu Shen Kuo Zhao the Department of Computer Science and Technology Jilin University the Department of Software Engineering Jilin University the Training Department Aviation University of Air Force

The lack of continuous connectivity and a complete path from source to destination makes node communication quite difficult in Delay-Tolerant Networks(DTNs). Most studies focus on routing problems in idealized network environments without considering social properties. Communication devices are carried by individuals in many DTNs; therefore, DTNs are unique social networks to some extent. To design efficient routing protocols for DTNs, it is important to analyze their social properties. In this paper, a more accurate and comprehensive metric for detecting the quality of the relationships between nodes is proposed, by considering the contact time, contact frequency, and contact regularity. An overlapping hierarchical community detection method is designed based on this new metric, and a tree structure is built. Furthermore, we exploit the overlapping community structure and the tree structure to provide message-forwarding paths from the source node to the destination *** simulation results show that our Routing method based on Overlapping hierarchical Community Detection(ROCD) achieves better delivery rate than SimBet and Bubble Rap, the classic routing protocols, without affecting the average delay.

关键词： Delay-Tolerant Network (DTN) social properties overlapping community hierarchical routing

Role of endovascular embolisation for curative treatment of intracranial non- Galenic pial arteriovenous fistula

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Stroke & Vascular Neurology 2021年第2期6卷 260-266页

作者： Hengwei Jin xiangyu meng Jiale Quan Yi Lu Youxiang Li Department of Interventional Neuroradiology Beijing Tiantan HospitalBeijingChina Interventional Neuroradiology department Beijing Neurosurgical InstituteBeijingChina Pediatric department Dongming People’s HospitalBeijingChina Department of Interventional Neuroradiology Beijing Neurosurgical InstituteBeijingChina

Background and purpose The safety and effectiveness of endovascular treatment for non-Galenic pial arteriovenous fistula(NGPAVF)is inadequately *** aim of this study is to explore the role of endovascular embolisation for curative treatment of *** and methods Patients with NGPAVF underwent endovascular treatment from January 2011 to November 2019 in our institution were retrospectively ***,clinical information,treatment details and clinical outcomes were *** associated with clinical outcomes were statistically *** Twenty patients were included,with a total of 22(2 patients have 2 fistulas)lesions.A total of 25 procedures were performed and 5 patients underwent 2 ***-up ranged from 3 to 84 months(mean=34.5 months).Thirteen(59.1%)lesions in 12(60.0%)patients acquired immediate occlusion after initial treatment(immediately occluded group)and follow-up confirmed the complete obliteration.A total of 17(77.3%)lesions in 15(75.0%)patients were cured at last *** maximal diameter of feeding arteries(p=0.04)and the maximal diameter of the varix(p=0.01)in immediately occluded group was smaller than non-immediately occluded *** number of feeding artery(p=0.004)and the maximal diameter of the varix(p<0.001)were much smaller in curative group than non-curative *** patients suffered procedure-related *** patients had an increased Modified Rankin Scale(mRS)and all patients had favourable clinical outcome(mRS≥2)at last *** Endovascular therapy plays an important role in curative treatment of *** with less feeding arteries and small varix may be easier to be cured by endovascular embolisation.

关键词： curative fistula treatment

Origin of Overpressure and its Effect on Hydrocarbon Enrichment in the Hinterland of Junggar Basin,NW China

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Acta Geologica Sinica(English Edition) 2024年第6期98卷 1511-1532页

作者： HAN Zaihua LIU Hua LI Jun CHENG Bin ZHANG Hongrui meng xiangyu National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)QingdaoShandong 266580China Laboratory for Marine Mineral Resources Qingdao Marine Science and Technology CenterQingdaoShandong266071China Petroleum Development Center Sinopec Shengli Oilfield CompanyDongyingShandong 257061China

Overpressure is widely developed in deep petroliferous strata in the hinterland of the Junggar ***,a comprehensive understanding of its origin and effect on hydrocarbon distribution and enrichment remains *** this study,we employ five empirical methods and comprehensive geological analysis to identify the origin of overpressure,and uncover the effect of overpressure on hydrocarbon *** results indicate that disequilibrium compaction is not a significant factor in overpressure ***,hydrocarbon generation,pressure transfer and diagenesis are the primary *** empirical methods support this *** is a positive correlation between overpressure intensity and source rock thickness and ***,widespread cross-formational migration of hydrocarbon bearing fluid occurred,with sandstone overpressure exceeding that of adjacent shale in non-source ***,there is a distinct transformation from smectite to illite near the top of *** generation pressurization and pressure transfer significantly effect hydrocarbon *** overpressure caused by hydrocarbon generation drives hydrocarbon migration and accumulation,establishing an optimal energy configuration between reservoir and cap *** play a crucial role in hydrocarbon vertical migration and pressure *** overpressure in reservoirs can reduce the porosity and permeability thresholds and enhance the charging capacity of oil and gas.

关键词： overpressure origin hydrocarbon generation pressure transfer diagenesis hydrocarbon enrichment Junggar Basin