检索结果-南通市图书馆

Maximum Orders of Extendable Actions on Surfaces

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2016年第1期32卷 54-68页

作者： Chao wang shi cheng wang Yi Mu ZHANG School of Mathematical Sciences Peking University

We determine the maximum order Eg of finite groups G acting on the closed surface E9 of genus g which extends over （S3, ∑g） for all possible embeddings ∑g → S3, where g 〉 1.

关键词： Symmetry of surface symmetry of 3-sphere extendable action

Finiteness of Mapping Degree Sets for 3-Manifolds

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2011年第5期27卷 807-812页

作者： Pierre DERBEZ Hong Bin SUN shi cheng wang Centre de Mathematiques et d'Informatique Technopole de Chateau-Gombert 39 rue Frdddric Joliot-Curie-13453 Marseille Cedex 13 France Department of Mathematics Princeton University Princeton NJ 08544 USA Department of Mathematics Peking University Beijing 100871 P. R. China

By constructing certain maps, this note completes the answer of the question： For which closed orientable 3-manifold N, is the set of mapping degrees D（M, N） finite for any closed orientable 3-manifold M？

关键词： 3-Manifolds mapping degrees finiteness

Cooperative interception with fast multiple model adaptive estimation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2021年第6期17卷 1905-1917页

作者： Shao-bo wang Yang Guo shi-cheng wang Zhi-guo Liu Shuai Zhang Xi’an Research Institution of Hi-Technology China Xi’an Research Institution of Hi-Technology Northwestern Polytechnical UniversityChina

For the case that two pursuers intercept an evasive target,the cooperative strategies and state estimation methods taken by pursuers can seriously affect the guidance accuracy for the target,which performs a bang For the case that two pursuers intercept an evasive target,the cooperative strategies and state estimation methods taken by pursuers can seriously affect the guidance accuracy for the target,which performs a bang-bang evasive maneuver with a random switching *** Fast multiple model adaptive estimation(Fast MMAE)algorithm,the cooperative guidance law takes detection configuration affecting the accuracy of interception into *** the detection error model related to the line-of-sight(LOS)separation angle of two interceptors,an optimal cooperative guidance law solving the optimization problem is designed to modulate the LOS separation angle to reduce the estimation error and improve the interception *** to the uncertainty of the target bang-bang maneuver switching time and the effective fitting of its multi-modal motion,Fast MMAE is introduced to identify its maneuver switching time and estimate the acceleration of the target to track and intercept the target *** designed cooperative optimal guidance law with Fast MMAE has better estimation ability and interception performance than the traditional guidance law and estimation method via Monte Carlo simulation.

关键词： Cooperative guidance Optimal control Fast multiple model adaptive estimation (fast MMAE) Bang-bang maneuver Switch time Detection configuration Estimation error

Virtual instrument for monitoring process of brush plating

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2004年第Z1期14卷 126-131页

作者： JING Xue-dong XU Bin-shi wang cheng-tao ZHU Sheng DONG shi-yun School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200030 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200030 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China

A virtual instrument(Ⅵ) was developed to monitor the technological parameters in the process of brush plating, including coating thickness, brush-plating current, current density, deposition rate, and brush plating voltage. Meanwhile two approaches were presented to improve the measurement accuracy of coating thickness. One of them aims at eliminating the random interferences by moving average filtering; while the other manages to calculate the quantity of electricity consumed accurately with rectangular integration. With these two approaches, the coating thickness can be measured in real time with higher accuracy than the voltage-frequency conversion method. During the process of plating all the technological parameters are displayed visually on the front panel of the Ⅵ. Once brush current or current density overruns the limited values, or when the coating thickness reaches the objective value, the virtual will alarm. With this Ⅵ, the solution consumption can be decreased and the operating efficiency is improved.

关键词： brush plating virtual instrument coating thickness measurement nano-composite coating

Molecular hexagram and octagram:Position determined 3D metallo-supermolecules and concentration-induced transformation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2021年第6期32卷 1911-1914页

作者： Tun Wu Zhiyuan Jiang Xiaobo Xue shi-cheng wang Mingzhao Chen Jun wang Haisheng Liu Jun Yan Yi-Tsu Chan Pingshan wang Institute of Environmental Research at Greater Bay Area Key Laboratory for Water Quality and Conservation of the Pearl River DeltaMinistry of EducationGuangzhou UniversityGuangzhou 510006China Department of Organic and Polymer Chemistry College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China Department of Chemistry National Taiwan UniversityTaipei 10617

The reaction of a metallo-organic ligand(LA)in which two"V"-shaped bisterpyridines attaching to metaposition of"X"-shaped tetraterpyridine via connectivity and Zn^(2+)ions gave rise to 3D supramolecular architectures:octagram(Zn_(8)LA_(4)).However,a position varied ligand(LB)in which two"V"-shaped bisterpyridines locating at the ortho-position of"X"-shaped tetraterpyridine afforded a different 3D hexagram(Zn_(6)LB_(3)).Full characterizations included NMR(^(1)H,^(13)C,^(2)D COSY,NOESY and DOSY),ESI-MS,TWIM-MS,TEM and *** resulted structures were directly determined by the position of two"V"-shaped bisterpyridines attaching to"X"-shaped tetraterpyridine.

关键词： Self-assembly Terpyridine Supramolecular transformation Metal-organic ligand Metalla-cage

Incidence and risk factors of delirium in critically ill patients after non-cardiac surgery

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2010年第8期123卷 993-999页

作者： shi cheng-mei wang Dong-xin CHEN Kai-sheng GU Xiu-e Department of Anesthesiology and Surgical Intensive Care Peking University First Hospital Beijing 100034 China

Background Delirium is a common and deleterious complication in critically ill patients after surgery. The purpose of this study was to determine the incidence and risk factors of delirium in critically ill patients after non-cardiac surgery, and to investigate the relationship between the serum cortisol level and the occurrence of postoperative delirium. Methods In a prospective cohort study, 164 consecutive patients who were admitted to the surgical intensive care unit after non-cardiac surgery were enrolled. Baseline characteristics and perioperative variables were collected. Blood samples were obtained on the first postoperative day and serum cortisol concentrations were measured. Delirium was assessed using the Nursing Delirium Screening Scale until the seventh postoperative day or the disappearance of delirious symptoms. Results Postoperative delirium occurred in 44.5% of patients （73 of 164）. The median time to first onset of delirium is 0 （range 0 to 5 days） and the median duration of delirium is 3 （1 to 13） days. Independent risk factors of postoperative delirium included increasing age （odds ratio （OR） 2.646, 95% confidence interval （C/） 1.431 to 4.890, P=-0.002）, a history of previous stroke （OR 4.499, 95%C/1.228 to 16.481, P=-0.023）, high Acute Physiology and Chronic Health Evaluation II score on surgical intensive care unite admission （OR 1.391, 95%C/1.201 to 1.612, P 〈0.001）, and high serum cortisol level on the 1st postoperative day （OR 3.381, 95%CI 1.690 to 6.765, P=-0.001）. The development of delirium was linked to higher incidence of postoperative complications （28.8% vs. 7.7%, P 〈0.001）, and longer duration of hospitalization （18 （7 to 74） days vs. 13 （3 to 48） days, P 〈0.001）. Conclusions Delirium was a frequent complication in critically ill patients after non-cardiac surgery. High serum cortisol level was associated with increased incidence of postoperative delirium.

关键词： delirium postoperative period incidence risk factors hydrocortisone

Detection and Recognition of Spray Code Numbers on Can Surfaces Based on OCR

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2025年第1期82卷 1109-1128页

作者： Hailong wang Junchao shi School of Computer Science Zhongyuan University of TechnologyZhengzhou450007China

A two-stage algorithm based on deep learning for the detection and recognition of can bottom spray codes and numbers is proposed to address the problems of small character areas and fast production line speeds in can bottom spray code number *** the coding number detection stage,Differentiable Binarization Network is used as the backbone network,combined with the Attention and Dilation Convolutions Path Aggregation Network feature fusion structure to enhance the model detection *** terms of text recognition,using the Scene Visual Text Recognition coding number recognition network for end-to-end training can alleviate the problem of coding recognition errors caused by image color distortion due to variations in lighting and background *** addition,model pruning and quantization are used to reduce the number ofmodel parameters to meet deployment requirements in resource-constrained environments.A comparative experiment was conducted using the dataset of tank bottom spray code numbers collected on-site,and a transfer experiment was conducted using the dataset of packaging box production *** experimental results show that the algorithm proposed in this study can effectively locate the coding of cans at different positions on the roller conveyor,and can accurately identify the coding numbers at high production line *** Hmean value of the coding number detection is 97.32%,and the accuracy of the coding number recognition is 98.21%.This verifies that the algorithm proposed in this paper has high accuracy in coding number detection and recognition.

关键词： Can coding recognition differentiable binarization network scene visual text recognition model pruning and quantification transport model

T cell interactions with microglia in immune-inflammatory processes of ischemic stroke

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第5期20卷 1277-1292页

作者： Yuxiao Zheng Zilin Ren Ying Liu Juntang Yan Congai Chen Yanhui He Yuyu shi Fafeng cheng Qingguo wang Changxiang Li Xueqian wang School of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijingChina Library Beijing University of Chinese MedicineBeijingChina Dongzhimen Hospital Beijing University of Chinese MedicineBeijingChina

The primary mechanism of secondary injury after cerebral ischemia may be the brain inflammation that emerges after an ischemic stroke,which promotes neuronal death and inhibits nerve tissue *** the first immune cells to be activated after an ischemic stroke,microglia play an important immunomodulatory role in the progression of the *** an ischemic stroke,peripheral blood immune cells(mainly T cells)are recruited to the central nervous system by chemokines secreted by immune cells in the brain,where they interact with central nervous system cells(mainly microglia)to trigger a secondary neuroimmune *** review summarizes the interactions between T cells and microglia in the immune-inflammatory processes of ischemic *** found that,during ischemic stroke,T cells and microglia demonstrate a more pronounced synergistic ***1,Th17,and M1 microglia can co-secrete proinflammatory factors,such as interferon-γ,tumor necrosis factor-α,and interleukin-1β,to promote neuroinflammation and exacerbate brain ***2,Treg,and M2 microglia jointly secrete anti-inflammatory factors,such as interleukin-4,interleukin-10,and transforming growth factor-β,to inhibit the progression of neuroinflammation,as well as growth factors such as brain-derived neurotrophic factor to promote nerve regeneration and repair brain *** interactions between microglia and T cells influence the direction of the subsequent neuroinflammation,which in turn determines the prognosis of ischemic stroke *** trials have been conducted on the ways to modulate the interactions between T cells and microglia toward anti-inflammatory communication using the immunosuppressant fingolimod or overdosing with Treg cells to promote neural tissue repair and reduce the damage caused by ischemic ***,such studies have been relatively infrequent,and clinical experience is still *** summary,in ischemic stroke,T cell subsets and activated micro

关键词： brain immune inflammation interaction ischemic stroke mechanism microglia neuron secondary injury T cells

在线全文

学校读者我要写书评

暂无评论

利用到时差分布图方法进行近场地表震源定位

地球物理学报 2017年第8期60卷 3119-3132页

作者：史鹏程王元游庆瑜中国科学院地质与地球物理研究所油气资源研究重点实验室北京100029 中国科学院大学北京100049

近场震源的高精度定位在工程建设与军事应用等方面意义重大且应用广泛,如炮弹落点定位或车辆追踪等.定位过程面临速度结构未知、高分辨率要求等问题,传统的震源定位方法有一定的局限性.本文将超声波检测中的时差分布图(Delta T Mapping... 详细信息

近场震源的高精度定位在工程建设与军事应用等方面意义重大且应用广泛,如炮弹落点定位或车辆追踪等.定位过程面临速度结构未知、高分辨率要求等问题,传统的震源定位方法有一定的局限性.本文将超声波检测中的时差分布图(Delta T Mapping,简称DTM)方法首次成功引入近场震源定位问题中.DTM定位法首先建立一个测区的到时差模型,然后基于此模型对新的震源进行定位.有两种建立模型的方法,(1)网格搜索法:对原有模型进行线性插值,得到更高分辨率的到时差分布模型;(2)统计定位法:利用高斯过程回归建立到时差数据与位置坐标之间的映射关系.本文在北京某郊区进行了炸点定位实验,在140 m×90 m的测试区域内,定位误差为0.5~5.1 m.结果表明,DTM方法是一种可靠、高精度、具有近实时性的近场震源定位方法.进一步利用接收点、源点互换,在获得高精度DTM同时,可大幅降低标定与数据分析成本.结合震源扫描法具有解决多目标定位问题的潜力.

关键词：震源定位到时差时差分布图法高斯过程回归震源扫描法