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GLOBAL CONVERGENCE OF A CAUTIOUS PROJECTION BFGS ALGORITHM FOR NONCONVEX PROBLEMS WITHOUT GRADIENT LIPSCHITZ CONTINUITY

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Acta Mathematica Scientia 2024年第5期44卷 1735-1746页

作者： Gonglin YUAN xiong zhao Jiajia YU School of Mathematics and Information Science Center for Applied Mathematics of Guangxi(Guangxi University)Guangxi UniversityNanning530004China

A cautious projection BFGS method is proposed for solving nonconvex unconstrained optimization *** global convergence of this method as well as a stronger general convergence result can be proven without a gradient Lipschitz continuity assumption,which is more in line with the actual problems than the existing modified BFGS methods and the traditional BFGS *** some additional conditions,the method presented has a superlinear convergence rate,which can be regarded as an extension and supplement of BFGS-type methods with the projection ***,the effectiveness and application prospects of the proposed method are verified by numerical experiments.

关键词： cautious BFGS nonconvex problems Lipschitz continuity projection technique global convergence

Design and experimental study of the end-effector for broccoli harvesting

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 137-144页

作者： xiong zhao Gangji Xu Pengfei Zhang Gaohong Yu Yadan Xu Faculty of Mechanical Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China Key Laboratory of Transplanting Equipment and Technology of Zhejiang Province Hangzhou 310018China Hangzhou vocational&Technical College Hangzhou 310018China

The end-effector is an important part of the broccoli harvesting *** at the physical characteristics of a large broccoli head and thick stem,a spherical cutting tool broccoli harvesting end-effector was designed in this ***,the physical characteristics of broccoli were tested,and physical parameters such as the broccoli head diameter and stem diameter of broccoli were *** maximum cutting force of broccoli stems under different cutting angles was ***,according to the physical characteristics and harvesting process of broccoli,the end-effector was designed,and the mathematical model of kinematics and dynamics was *** on the results of dynamic analysis,the end-effector rod was optimized,and the unilateral width of the slider was 40 mm,the length of the connecting rod was 120 mm,and the length of the crank was 42 *** mechanism needed an external driving force of 140.54 N to cut the broccoli ***,a 32 mm cylinder with a load rate of 50%was selected as the power ***,the feasibility of the broccoli harvesting end-effector was verified by the harvesting *** showed that the overall harvesting success rate of the end-effector is 93.3%,and the smoothness rate of the stem section is 83.3%.The harvesting performance of the broccoli end-effector was *** lays a foundation for agricultural robots to harvest broccoli.

关键词： harvesting robot broccoli end-effector dynamic analysis mechanism optimization

Optimization design and experiment of the variable differential gear train planting mechanism

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 85-93页

作者： xiong zhao Ziwei Liu Yuanwu Jia Xingxiao Ma Pengfei Zhang Jianneng Chen School of Mechanical Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China Xi’an International University Engineering College Xi’an 710077China Hangzhou Vocational&Technical College Hangzhou 310018China

In order to improve the adaptability of the planting mechanism for different plant spacings,a variable differential gear train planting mechanism based on precise pose and trajectory control was proposed by combining the open chain 2R rod group and the variable differential gear *** to the pose requirements of receiving seedling point,transporting seedling point and planting point,three precise pose points of constrained planting trajectory were *** the three-position motion generation structural synthesis method,combined with computer-aided optimization design software,a set of mechanism parameters that meet the planting requirements were *** on the optimized mechanism parameters,by only changing the coordinates of two trajectory shape control points,three planting trajectories with key point position information adapted to 300 mm,400 mm and 500 mm plant spacing were obtained by interpolation,and three pairs of total transmission ratio of three groups of variable differential gear trains were *** distributing the total transmission ratio of the mechanism,the fixed axis gear train and the differential gear train are *** fixed axis gear train included a pair of non-circular gear pairs and a pair of positive gear pairs,which were convenient for disassembly and *** former drives the sun gear at variable speed,and the latter drives the planet carrier at uniform *** on this structure,the transmission ratio of the positive gear pair is-1,and the transmission ratio of the differential gear train is *** sub-transmission ratio of the single-stage non-circular gear pair was calculated and the pitch curves of three pairs of noncircular gears were *** pairs of non-circular gear pairs with different transmission ratios were replaced in turn and three sets of planting mechanisms were modeled in three *** virtual prototype motion simulation was completed by ADAMS software,and the p

关键词： plant spacing planting mechanism variable differential gear train precise pose trajectory control parameter optimization

Design and experimental research on the sweet potato seedling transplanting mechanism of the planetary gear train with deformed elliptical gear transmission

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International Journal of Agricultural and Biological Engineering 2024年第3期17卷 91-99页

作者： Bingliang Ye Yuxuan Ye Haili Zhou Gaohong Yu xiong zhao Bin Deng Faculty of Mechanical Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China Zhejiang Province Key Laboratory of Transplanting Equipment and Technology Hangzhou 310018China Key Laboratory of Agricultural Equipment for Hilly and Mountainous Areas in Southeastern China(Co-construction by Ministry and Province) Ministry of Agriculture and Rural AffairsHangzhou 310018China

Aiming at the lack of suitable machines for sweet potato seedling transplanting in China,and according to the agronomic requirements for the horizontal insertion method of sweet potato seedling,a new sweet potato seedling transplanting mechanism of planetary gear train was proposed based on the non-uniform transmission of deformed elliptical *** working principle of the transplanting mechanism was analyzed,and the kinematics modeling and analysis of the mechanism were carried *** study established the numerical objectives of the transplanting mechanism and applied the theory of membership function to establish a mathematical model for the parameter-guided optimization design of the transplanting *** parameter-guided optimization design software was developed to obtain a set of optimal mechanism parameters that satisfied the motion trajectory of sweet potato transplanting and the posture of the transplanting *** on the optimized parameters,the structure of the transplanting mechanism was designed,and a virtual prototype of the mechanism was created,whereby a virtual motion simulation of the transplanting mechanism was conducted to verify the correctness of the kinematics model and design of the *** high-speed photographic kinematics test of the mechanism prototype and sweet potato seedling transplanting tests were conducted to test the mechanism’s kinematic characteristics and transplanting *** test results show that the test trajectory of the mechanism and test posture of the transplanting arm are almost consistent with the theoretical and simulation trajectory,meeting the agronomic requirements of the horizontal insertion method of sweet potato seedling;And when the rotary speed of the mechanism are 20 r/min and 30 r/min,the average success ratios of sweet potato seedlings transplanting are 90%and 82%,respectively,which prove the application feasibility of the mechanism in the practical machines.

关键词： sweet potato seedling transplanter transplanting mechanism deformed elliptical gear transmission kinematics analysis membership function optimization design

Clinical outcome and prognostic factors of T4N0M0 colon cancer after R0 resection:A retrospective study

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1869-1877页

作者： Bang Liu zhao-xiong Zhang Xin-Yang Nie Wei-Lin Sun Yong-Jia Yan Wei-Hua Fu Department of General Surgery Tianjin Medical University General HospitalTianjin Medical UniversityTianjin 300052China

BACKGROUND Paradoxically,patients with T4N0M0(stage II,no lymph node metastasis)colon cancer have a worse prognosis than those with T2N1-2M0(stage III).However,no previous report has addressed this *** To screen prognostic risk factors for T4N0M0 colon cancer and construct a prognostic nomogram model for these *** Two hundred patients with T4N0M0 colon cancer were treated at Tianjin Medical University General Hospital between January 2017 and December 2021,of which 112 patients were assigned to the training cohort,and the remaining 88 patients were assigned to the validation *** between the training and validation groups were *** training cohort was subjected to multi-variate analysis to select prognostic risk factors for T4N0M0 colon cancer,followed by the construction of a nomogram *** The 3-year overall survival(OS)rates were 86.2%and 74.4%for the training and validation cohorts,***(P=0.000),T stage(P=0.001),right hemicolon(P=0.025),irregular review(P=0.040),and carbohydrate antigen 199(CA199)(P=0.011)were independent risk factors of OS in patients with T4N0M0 colon cancer.A nomogram model with good concordance and accuracy was *** Enterostomy,T stage,right hemicolon,irregular review,and CA199 were independent risk factors for OS in patients with T4N0M0 colon *** nomogram model exhibited good agreement and accuracy.

关键词： T4N0M0 colon cancer Prognosis Multivariate analysis Nomogram Colon cancer

Heavy ion energy influence on multiple-cell upsets in small sensitive volumes:from standard to high energies

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Nuclear Science and Techniques 2024年第5期35卷 109-121页

作者： Yang Jiao Li-Hua Mo Jin-Hu Yang Yu-Zhu Liu Ya-Nan Yin Liang Wang Qi-Yu Chen Xiao-Yu Yan Shi-Wei zhao Bo Li You-Mei Sun Pei-xiong zhao Jie Liu Institute of Modern Physics Chinese Academy of ScienceLanzhou 730000China University of Chinese Academy of Science Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China China Electronics Technology Group Corporation No.58 Research Institute Wuxi 214000China Beijing Microelectronics Technology Institute Beijing 100084China Institute of Microelectronics Chinese Academy of SciencesBeijing 100029China Key Laboratory of Science and Technology on Silicon Devices Chinese Academy of SciencesBeijing 100029China

The 28 nm process has a high cost-performance ratio and has gradually become the standard for the field of radiation-hardened ***,owing to the minimum physical gate length of only 35 nm,the physical area of a standard 6T SRAM unit is approximately 0.16μm^(2),resulting in a significant enhancement of multi-cell charge-sharing ***-cell upsets(MCUs)have become the primary physical mechanism behind single-event upsets(SEUs)in advanced nanometer node *** range of ionization track effects increases with higher ion energies,and spacecraft in orbit primarily experience SEUs caused by high-energy ***,ground accelerator experiments have mainly obtained low-energy ion irradiation ***,the impact of ion energy on the SEU cross section,charge collection mechanisms,and MCU patterns and quantities in advanced nanometer devices remains *** this study,based on the experimental platform of the Heavy Ion Research Facility in Lanzhou,low-and high-energy heavy-ion beams were used to study the SEUs of 28 nm SRAM *** influence of ion energy on the charge collection processes of small-sensitive-volume devices,MCU patterns,and upset cross sections was obtained,and the applicable range of the inverse cosine law was *** findings of this study are an important guide for the accurate evaluation of SEUs in advanced nanometer devices and for the development of radiation-hardening techniques.

关键词： 28 nm static random access memory(SRAM) Energy effects Heavy ion Multiple-cell upset(MCU) Charge collection Inverse cosine law

Manganese oxide and derivative-modified materials in advanced oxidation processes:A review of modification enhancement and activation mechanisms

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Chinese Chemical Letters 2024年第3期35卷 40-51页

作者： Si Sun Shuang Song Shuai Yang Yong-Li He Yang Shi Peng Zhou zhao-kun xiong Yang Liu Heng Zhang Ye Du Chuan-Shu He Bo Lai State Key Laboratory of Hydraulics and Mountain River Engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China Sino-German Centre for Water and Health Research Sichuan UniversityChengdu 610065China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaSichuanChengdu 610054China

Manganese oxides(MNO_(x)),as low-toxicity and high-abundance catalysts,have been demonstrated to hold great promise for application in advanced oxidation processes(AOPs).However,further application of this material is restricted due to its unsatisfactory oxidant activation ***,recently remarkable research on deep activation mechanisms and modification of MNO_(x)have been undertaken to improve its ***,modification enhancement mechanisms of MNO_(x)to efficiently degrade various organic contaminants were discussed and highlighted,including metal doping,coupling with other metal oxides,composite with carbonaceous material,and compounding with other *** activation mechanisms of different MNO_(x)and derivative-modified material(such as doped MNO_(x),metal oxide-MNO_(x)hybrids,and MNO_(x)-carbonaceous material hybrids)were summarized in great details,which was specifically categorized into both radical and non-radical *** effects of pH,inorganic ions,and natural organic matter on degradation reactions are also ***,future research directions and perspectives are presented to provide a clear interpretation on the MNO_(x)initiated AOPs.

关键词： Manganese oxide Derivative-modified materials Modification enhancement mechanisms Advanced oxidation process Activation mechanism

Liver transplantation following two conversions in a patient with huge hepatocellular carcinoma and portal vein invasion:A case report

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World Journal of Gastroenterology 2024年第36期30卷 4071-4077页

作者： Li-Cong Liang Wen-Sou Huang zhao-xiong Guo Hong-Ji You Yong-Jian Guo Ming-Yue Cai Li-Teng Lin Guo-Ying Wang Kang-Shun Zhu Department of Minimally Invasive Interventional Radiology The Second Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510260Guangdong ProvinceChina Department of Nuclear Medicine The Second Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510260Guangdong ProvinceChina Department of Hepatobiliary Surgery The First Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510120Guangdong ProvinceChina

BACKGROUND Surgical resection and liver transplantation(LT)are the most effective curative options for hepatocellular carcinoma(HCC).However,few patients with huge HCC(>10 cm in diameter),especially those with portal vein tumor thrombus(PVTT),can receive these *** internal radiation therapy(SIRT)can be used as a conversion therapy for them because it has the dual benefit of shrinking tumors and increasing residual hepatic ***,in patients with huge HCC,high lung absorbed dose often prevents them from receiving *** SUMMARY A 35-year-old man was admitted because of emaciation and pain in the hepatic region for about 1 *** computed tomography scan showed a 20.2 cm×19.8 cm tumor located in the right lobe–left medial lobes with right portal vein and right hepatic vein *** the pathological type of HCC was confirmed by biopsy,two conversions were *** first one was drug-eluting bead transarterial chemoembolization plus hepatic arterial infusion chemotherapy and lenvatinib and sintilimab,converted to SIRT,and the second one was sequential SIRT with continued systemic *** tumor size significantly decreased from 20.2 cm×19.8 cm to 16.2 cm×13.8 cm,then sequentially to 7.8 cm×6.8 *** the meantime,the ratio of spared volume to total liver volume increased gradually from 34.4%to 55.7%,then to 62.9%.Furthermore,there was visualization of the portal vein,indicating regression of the tumor ***,owing to the new tumor in the left lateral lobe,the patient underwent LT instead of resection without major *** Patients with inoperable huge HCC with PVTT could be converted to SIRT first and accept surgery sequentially.

关键词： Hepatocellular carcinoma Two conversions Liver transplantation Yttrium-90 resin microspheres Transarterial chemoembolization Hepatic arterial infusion chemotherapy Case report

弹性支承块轨道结构病害对钢轨竖向位移影响研究

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城市轨道交通研究 2024年第S1期27卷 37-41页

作者：赵雄上海地铁维护保障有限公司工务分公司上海200233

[目的]弹性支承块轨道结构因其具有较强的减振降噪特性,在城市轨道交通中被广泛应用。但弹性支承块轨道结构病害对钢轨竖向位移影响较大,需对其进行研究,以有效整治该类病害。[方法]弹性支承块轨道结构主要病害为支承块空吊和扣件失效... 详细信息

[目的]弹性支承块轨道结构因其具有较强的减振降噪特性,在城市轨道交通中被广泛应用。但弹性支承块轨道结构病害对钢轨竖向位移影响较大,需对其进行研究,以有效整治该类病害。[方法]弹性支承块轨道结构主要病害为支承块空吊和扣件失效。基于上海轨道交通8号线弹性支承块轨道结构,建立了弹性支承块轨道静力学模型,分析了无缝线路和有缝线路轨道在列车静荷载下支承块空吊、扣件失效对钢轨竖向位移的影响。[结果及结论]支承块空吊病害会对钢轨竖向位移产生较大影响。对于无缝线路,无支承块空吊病害时的钢轨竖向位移为1.441 mm;对于有缝线路,无支承块空吊病害时的钢轨竖向位移为1.530 mm。发生支承块空吊时,随着支承块空吊量的增加,钢轨竖向最大位移先增加后趋于稳定。在扣件完全失效情况下,钢轨竖向位移会随着失效扣件套数的增加而成倍增加,有缝线路钢轨竖向位移比无缝线路的大0.056~1.186 mm。扣件刚度折减越少,对其他位置钢轨竖向位移影响越小。

关键词：城市轨道交通轨道结构支承块空吊扣件失效钢轨竖向位移