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Influence of typhoon MITAG on the Kuroshio intrusion in the Luzon Strait during early fall 2019
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作者 meng liu Fukang Qi +2 位作者 Yunpeng Lin Yuping Yang Jingping Xu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第9期70-80,共11页
Typhoons in the western Pacific have a significant impact on the transport of heat,salt and particles through the Luzon Strait.However,there are very limited field observations of this impact because of extreme diffic... Typhoons in the western Pacific have a significant impact on the transport of heat,salt and particles through the Luzon Strait.However,there are very limited field observations of this impact because of extreme difficulties and even dangers for ship-based measurements during the rough weather.Here,we present the preliminary results from analyzing a dataset collected by a glider deployed west of the Luzon Strait a few days prior to the arrival of typhoon MITAG.The gilder data revealed an abnormally salinity(>34.8)subsurface water apparently sourced from Kuroshio intrusion during the typhoon.When typhoon MITAG traveled on the east of the Luzon Strait,the positive wind stress curl strengthened the cyclonic eddy and weakened the anti-cyclonic eddy.This led to a slowdown of Kuroshio and made its intrusion easier.The main axis of the Kuroshio at the northern part of the strait shifted westward after the typhoon and did not return to its original position until a week later.The Ekman transport from persistent northerly wind of typhoon MITAG was significant,but its importance in enhancing the Kuroshio intrusion is only secondary relative to the eddies variations. 展开更多
关键词 TYPHOON GLIDER Kuroshio intrusion Luzon Strait
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UKF‐MOT:An unscented Kalman filter‐based 3D multi‐object tracker
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作者 meng liu Jianwei Niu Yu liu 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第4期1031-1041,共11页
Multi‐object tracking in autonomous driving is a non‐linear problem.To better address the tracking problem,this paper leveraged an unscented Kalman filter to predict the object's state.In the association stage,t... Multi‐object tracking in autonomous driving is a non‐linear problem.To better address the tracking problem,this paper leveraged an unscented Kalman filter to predict the object's state.In the association stage,the Mahalanobis distance was employed as an affinity metric,and a Non‐minimum Suppression method was designed for matching.With the detections fed into the tracker and continuous‘predicting‐matching’steps,the states of each object at different time steps were described as their own continuous trajectories.We conducted extensive experiments to evaluate tracking accuracy on three challenging datasets(KITTI,nuScenes and Waymo).The experimental results demon-strated that our method effectively achieved multi‐object tracking with satisfactory ac-curacy and real‐time efficiency. 展开更多
关键词 autonomous vehicle TRANSPORTATION
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Characteristics and Analysis of Dominant Diseases in Jing Nationality Medicine
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作者 meng liu Yirong Gan +5 位作者 Quan Zhao Xin Huang Huiqin Ge Hongliang Tang Xiaowei He Yuan Yu 《Open Journal of Internal Medicine》 2023年第4期371-380,共10页
Jing medicine occupies a very prominent position in the traditional culture of the Chinese nation and has unique advantages. Through the literature review of Jing medicine, the author has a deeper understanding of Jin... Jing medicine occupies a very prominent position in the traditional culture of the Chinese nation and has unique advantages. Through the literature review of Jing medicine, the author has a deeper understanding of Jing medicine in Guangxi. This paper mainly shows the traditional characteristic medicine culture of the Jing nationality and discusses the characteristic therapy and medication characteristics of Jing nationality medicine, which is conducive to the improvement of people’s cognition of Jing nationality medicine and the development and innovation of Jing nationality medicine. 展开更多
关键词 Jing Medicine Unique Advantages Characteristic Therapy Medication Characteristics
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Ferroptosis is involved in deoxynivalenol-induced intestinal damage in pigs 被引量:5
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作者 meng liu Lei Zhang +6 位作者 Yixin Mo Jiahuan Li Jiacheng Yang Juan Wang Niel Alexander Karrow Hao Wu Lvhui Sun 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第4期1408-1417,共10页
Background Deoxynivalenol(DON)is a widespread issue for feed and food safety,leading to animal and human health risks.The objective of this study was to determine whether ferroptosis is involved in DON-induced intesti... Background Deoxynivalenol(DON)is a widespread issue for feed and food safety,leading to animal and human health risks.The objective of this study was to determine whether ferroptosis is involved in DON-induced intestinal injury in piglets.Three groups of 21-day-old male weanling piglets(n 4,serum and small intestines were=7/group)were fed a control diet,or diet adding 1.0 or 3.0 mg DON/kg.At week collected to assay for biochemistry,histology,redox status and ferroptosis-related genes expression.In addition,the involvement of ferroptosis and the role of FTL gene in DON-induced cell death were further verified in the IPEC-J2 cells.Results Compared to the control,dietary supplementation of DON at 1.0 and 3.0 mg/kg induced different degrees of damage in the duodenum,jejunum and ileum,and increased(P<0.05)serum lipopolysaccharide concentration by 46.2%-51.4%.Dietary DON supplementation at 1.0 and(or)3.0 mg/kg increased(P<0.05)concentrations of malondialdehyde(17.4%-86.5%)and protein carbonyl by 33.1%-92.3%in the duodenum,jejunum and ileum.In addition,dietary supplemented with DON upregulated(P<0.05)ferroptotic gene(DMT1)and anti-ferroptotic genes(FTL and FTH1),while downregulated(P<0.05)anti-ferroptotic genes(FPN,FSP1 and CISD1)in the duodenum of the porcine.Furthermore,the in vitro study has demonstrated that deferiprone,a potent ferroptotic inhibitor,mitigated(P<0.05)DON-induced cytotoxicity in porcine small intestinal IPEC-J2 cells.Additionally,deferiprone prevented or alleviated(P<0.05)the dysregulation of ferroptosis-related genes(ACSL4 and FTL)by DON in IPEC-J2 cells.Moreover,specific siRNA knockdown FTL gene expression compromised the DON-induced cell death in IPEC-J2 cells.Conclusions In conclusion,this study revealed that ferroptosis is involved in DON-induced intestinal damage in porcine,and sheds a new light on the toxicity of DON to piglets. 展开更多
关键词 DEOXYNIVALENOL Ferroptosis INTESTINE PIGLETS TOXICITY
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结直肠癌肠造口患者的健康信息规避与健康促进行为的研究
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作者 刘萌 李梦飞 +3 位作者 王淑云 杨富国 陈德鑫 刘景哲 《世界华人消化杂志》 CAS 2023年第17期732-741,共10页
背景肠造口术是目前结直肠癌的主要治疗方式.健康促进行为可以提高肠造口患者的生活质量,对维持患者的健康状态具有重要意义,而健康信息规避会驱使患者回避健康风险信息,不利于自身健康.本研究猜想肠造口患者健康信息规避是健康促进行... 背景肠造口术是目前结直肠癌的主要治疗方式.健康促进行为可以提高肠造口患者的生活质量,对维持患者的健康状态具有重要意义,而健康信息规避会驱使患者回避健康风险信息,不利于自身健康.本研究猜想肠造口患者健康信息规避是健康促进行为的主要因素.目的了解结直肠癌肠造口患者健康信息规避和健康促进行为现状,并探讨两者之间的关系,为提高肠造口患者的预后及生活质量提供参考依据.方法采用便利抽样法,选取青岛市某三甲医院造口门诊就诊的205例肠造口患者作为研究对象,采用一般资料调查表、健康信息规避量表、健康促进生活方式量表Ⅱ对患者进行调查.结果肠造口患者的健康信息规避得分为(25.99±8.81)分,105例(56.10%)肠造口患者存在不同程度的健康信息规避行为,其中64例(31.20%)患者为轻度规避,41例(24.90%)患者为重度规避.患者的健康促进行为得分(126.19±15.32)分,总体处于一般水平.健康信息规避与健康促进行为呈负相关.多元回归分析显示,健康信息规避行为是健康促进行为的显著影响因素.结论肠造口患者的健康信息规避行为有待改善,健康促进行为有待提高.医护人员可了解患者在接收健康信息过程中的阻碍因素,帮助患者有效应对健康信息规避,提高患者的健康行为及生活质量. 展开更多
关键词 结直肠癌 肠造口 健康信息规避 健康促进行为 健康信息
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A bi-functional strategy involving surface coating and subsurface gradient co-doping for enhanced cycle stability of LiCoO_(2) at 4.6 V 被引量:2
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作者 Yun He Xiaoliang Ding +7 位作者 Tao Cheng Hongyu Cheng meng liu Zhijie Feng Yijia Huang menghan Ge Yingchun Lyu Bingkun Guo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期553-560,I0014,共9页
Layered LiCoO_(2)(LCO)acts as a dominant cathode material for lithium-ion batteries(LIBs)in 3C products because of its high compacted density and volumetric energy density.Although improving the high cutoff voltage is... Layered LiCoO_(2)(LCO)acts as a dominant cathode material for lithium-ion batteries(LIBs)in 3C products because of its high compacted density and volumetric energy density.Although improving the high cutoff voltage is an effective strategy to increase its capacity,such behavior would trigger rapid capacity decay due to the surface or/and structure degradation.Herein,we propose a bi-functional surface strategy involving constructing a robust spinel-like phase coating layer with great integrity and compatibility to LiCoO_(2) and modulating crystal lattice by anion and cation gradient co-doping at the subsurface.As a result,the modified LiCoO_(2)(AFM-LCO)shows a capacity retention of 80.9%after 500 cycles between 3.0and 4.6 V.The Al,F,Mg enriched spinel-like phase coating layer serves as a robust physical barrier to effectively inhibit the undesired side reactions between the electrolyte and the cathode.Meanwhile,the Al,F,Mg gradient co-doping significantly enhances the surficial structure stability,suppresses Co dissolution and oxygen release,providing a stable path for Li-ions mobility all through the long-term cycles.Thus,the surface bi-functional strategy is an effective method to synergistically improve the electrochemical performances of LCO at a high cut-off voltage of 4.6 V. 展开更多
关键词 Lithium-ion batteries 4.6 V-LiCoO_(2) Surface modification Gradient co-doping Interfacial stability
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Biomimetic biomineralization nanoplatform-mediated differentiation therapy and phototherapy for cancer stem cell inhibition and antitumor immunity activation
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作者 Shan Gao meng liu +7 位作者 Dongzhu liu Xinru Kong Yuelin Fang Yingying Li Hang Wu Jianbo Ji Xiaoye Yang Guangxi Zhai 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2023年第5期164-184,共21页
Growing evidence suggests that the presence of cancer stem cells(CSCs)is a major challenge in current tumor treatments,especially the transition from non-CSCs to differentiation of CSCs for evading conventional therap... Growing evidence suggests that the presence of cancer stem cells(CSCs)is a major challenge in current tumor treatments,especially the transition from non-CSCs to differentiation of CSCs for evading conventional therapies and driving metastasis.Here we propose a therapeutic strategy of synergistic differentiation therapy and phototherapy to induce differentiation of CSCs into mature tumor cells by differentiation inducers and synergistic elimination of them and normal cancer cells through phototherapy.In this work,we synthesized a biomimetic nanoplatform loaded with IR-780 and all-trans retinoic acid(ATRA)via biomineralization.This method can integrate aluminum ions into small-sized protein carriers to form nanoclusters,which undergo responsive degradation under acidic conditions and facilitate deep tumor penetration.With the help of CSC differentiation induced by ATRA,IR-780 inhibited the self-renewal of CSCs and cancer progression by generating hyperthermia and reactive oxygen species in a synergistic manner.Furthermore,ATRA can boost immunogenic cell death induced by phototherapy,thereby strongly causing a systemic anti-tumor immune response and efficiently eliminating CSCs and tumor cells.Taken together,this dual strategy represents a new paradigm of targeted eradication of CSCs and tumors by inducing CSC differentiation,improving photothermal therapy/photodynamic therapy and enhancing antitumor immunity. 展开更多
关键词 Cancer stem cells Differentiation therapy PHOTOTHERAPY BIOMINERALIZATION Immunogenic cell death
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Efficient ion acceleration driven by a Laguerre–Gaussian laser in near-critical-density plasma
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作者 高嘉祥 刘梦 王伟民 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第10期542-547,共6页
Laser-driven ion accelerators have the advantages of compact size,high density,and short bunch duration over conventional accelerators.Nevertheless,it is still challenging to generate ion beams with quasi-monoenergeti... Laser-driven ion accelerators have the advantages of compact size,high density,and short bunch duration over conventional accelerators.Nevertheless,it is still challenging to generate ion beams with quasi-monoenergetic peak and low divergence in experiments with the current ultrahigh intensity laser and thin target technologies.Here we propose a scheme that a Laguerre–Gaussian laser irradiates a near-critical-density(NCD)plasma to generate a quasi-monoenergetic and low-divergence proton beam.The Laguerre–Gaussian laser pulse in an NCD plasma excites a moving longitudinal electrostatic field with a large amplitude,and it maintains the inward bowl-shape for dozens of laser durations.This special distribution of the longitudinal electrostatic field can simultaneously accelerate and converge the protons.Our particle-in-cell(PIC)simulation shows that the efficient proton acceleration can be realized with the Laguerre–Gaussian laser intensity ranging from 3.9×10^(21)W·cm^(-2)–1.6×10^(22)W·cm^(-2)available in the near future,e.g.,a quasi-monoenergetic proton beam with peak energy~115 MeV and divergence angles less than 5°can be generated by a 5.3×10^(21)W·cm^(-2)pulse.This work could provide a reference for the high-quality ion beam generation with PWclass laser systems available recently. 展开更多
关键词 Laguerre–Gaussian laser laser-driven ion acceleration particle-in-cell simulations near-critical-density plasma
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Salient Object Detection Based on a Novel Combination Framework Using the Perceptual Matching and Subjective-Objective Mapping Technologies
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作者 Jian Han Jialu Li +3 位作者 meng liu Zhe Ren Zhimin Cao Xingbin liu 《Journal of Beijing Institute of Technology》 EI CAS 2023年第1期95-106,共12页
The integrity and fineness characterization of non-connected regions and contours is a major challenge for existing salient object detection.The key to address is how to make full use of the subjective and objective s... The integrity and fineness characterization of non-connected regions and contours is a major challenge for existing salient object detection.The key to address is how to make full use of the subjective and objective structural information obtained in different steps.Therefore,by simulating the human visual mechanism,this paper proposes a novel multi-decoder matching correction network and subjective structural loss.Specifically,the loss pays different attentions to the foreground,boundary,and background of ground truth map in a top-down structure.And the perceived saliency is mapped to the corresponding objective structure of the prediction map,which is extracted in a bottom-up manner.Thus,multi-level salient features can be effectively detected with the loss as constraint.And then,through the mapping of improved binary cross entropy loss,the differences between salient regions and objects are checked to pay attention to the error prone region to achieve excellent error sensitivity.Finally,through tracking the identifying feature horizontally and vertically,the subjective and objective interaction is maximized.Extensive experiments on five benchmark datasets demonstrate that compared with 12 state-of-the-art methods,the algorithm has higher recall and precision,less error and strong robustness and generalization ability,and can predict complete and refined saliency maps. 展开更多
关键词 salient object detection subjective-objective mapping perceptional separation and matching error sensitivity non-connected region detection
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德谷胰岛素与甘精胰岛素治疗口服药物控制不佳的2型糖尿病患者疗效对比 被引量:4
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作者 孟柳 张燕 +1 位作者 杜梦茹 蒋升 《新疆医学》 2022年第9期1008-1010,1070,共4页
目的探讨口服足量二甲双胍血糖控制不佳的2型糖尿病患者联合德谷胰岛素或甘精胰岛素治疗2型糖尿病的临床疗效及安全性。方法选取2019年1月-2020年1月于本院内分泌科就诊的125例2型糖尿病患者,使用足量二甲双胍治疗三个月以上糖化血红蛋... 目的探讨口服足量二甲双胍血糖控制不佳的2型糖尿病患者联合德谷胰岛素或甘精胰岛素治疗2型糖尿病的临床疗效及安全性。方法选取2019年1月-2020年1月于本院内分泌科就诊的125例2型糖尿病患者,使用足量二甲双胍治疗三个月以上糖化血红蛋白均不达标,以糖化血红蛋白7.5%为切点,按照就诊顺序分为二甲双胍联合德谷胰岛素组(观察组)和甘精胰岛素联合二甲双胍组(对照组)。其中,观察组61例,对照组64例,均治疗18周。随访内容包括FPG、2h-PG、HbA1C、体重以及胰岛素用量和低血糖事件数量、血糖波动;采用SPSS 18.0软件进行t检验和χ^(2)检验。结果治疗前两组患者空腹血糖、早餐后2h血糖和糖化血红蛋白水平比较,差异均无统计学意义(P>0.05)。治疗18周后,早餐后2h血糖、糖化血红蛋白均无统计学差异(P>0.05),空腹血糖差异有统计学意义(P<0.05)。观察组的低血糖发生率[1.6%]低于对照组[6.25%],胰岛素用量(19.25±3.64)U低于对照组(32.67±5.81)U,有统计学意义(P<0.05)。两组均无严重低血糖反应发生,血糖波动有统计学差异(P<0.05)。结论二甲双胍联合德谷胰岛素治疗2型糖尿病,降糖效果好、安全性高,低血糖风险低,患者生活质量较高。 展开更多
关键词 甘精胰岛素 德谷胰岛素 2型糖尿病
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智能制造总体架构探析 被引量:22
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作者 孟柳 延建林 +4 位作者 董景辰 韦莎 李瑞琪 臧冀原 周源 《中国工程科学》 CSCD 北大核心 2018年第4期23-28,共6页
智能制造是一个不断演进的大系统,涵盖了产品、制造、服务全生命周期中所涉及的理论、方法、技术和应用。面对智能制造不断涌现的新技术、新理念、新模式,迫切需要总结提出智能制造系统架构,以更好地指导智能制造落地实施。本文从价值... 智能制造是一个不断演进的大系统,涵盖了产品、制造、服务全生命周期中所涉及的理论、方法、技术和应用。面对智能制造不断涌现的新技术、新理念、新模式,迫切需要总结提出智能制造系统架构,以更好地指导智能制造落地实施。本文从价值维、技术维和组织维三个维度构建了中国智能制造总体架构,并分别与美国、德国、日本智能制造相关系统架构做了横向比较。智能制造总体架构的技术维反映了智能制造以两化融合为主线,价值维体现了智能制造的主体是制造活动,组织维强调了智能制造要以人为本。 展开更多
关键词 智能制造 总体架构 智能转型 优化升级
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智能制造的三个基本范式:从数字化制造、“互联网+”制造到新一代智能制造 被引量:66
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作者 臧冀原 王柏村 +1 位作者 孟柳 周源 《中国工程科学》 CSCD 北大核心 2018年第4期13-18,共6页
本文简述了研究智能制造范式的重要意义,智能制造的内涵和发展历程,综合智能制造相关范式总结出智能制造三个基本范式:数字化制造、数字化网络化制造——"互联网+"制造、数字化网络化智能化制造——新一代智能制造。阐述了三... 本文简述了研究智能制造范式的重要意义,智能制造的内涵和发展历程,综合智能制造相关范式总结出智能制造三个基本范式:数字化制造、数字化网络化制造——"互联网+"制造、数字化网络化智能化制造——新一代智能制造。阐述了三种基本范式的内涵、特征。我国应从数字化"补课"做起,进一步夯实智能制造发展的基础;今后一阶段应重点发展"互联网+"制造,并行推进三种基本范式;新一代智能制造将从根本上引领和推进第四次工业革命,为我国实现制造业换道超车、跨越发展带来了历史性机遇。 展开更多
关键词 基本范式 数字化制造 “互联网+”制造 新一代智能制造
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近视的病因研究新进展 被引量:22
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作者 慕璟玉 王雁 +2 位作者 浏梦 张芮 高云仙 《国际眼科杂志》 CAS 北大核心 2021年第10期1746-1750,共5页
近年来,随着社会经济的发展、科技的进步及生活方式的改变,近视发病率逐年提高且有低龄化趋势。且随着新型冠状病毒肺炎(corona virus disease 2019,COVID-19)的爆发,儿童青少年长时间近距离地网络上课加速了近视发生发展的速度。近视... 近年来,随着社会经济的发展、科技的进步及生活方式的改变,近视发病率逐年提高且有低龄化趋势。且随着新型冠状病毒肺炎(corona virus disease 2019,COVID-19)的爆发,儿童青少年长时间近距离地网络上课加速了近视发生发展的速度。近视所导致的视力障碍以及高度近视引起的严重并发症已经严重影响到人们的生活、学习和工作质量。因此,世界卫生组织与国际防盲协会及我国卫生部门已将儿童青少年近视的防控工作提上日程。然而其病因复杂,现多认为与遗传、环境等因素有关,本文就此展开简要论述。 展开更多
关键词 近视 病因 遗传 环境 综述
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“三权分置”下土地经营权抵押的法律困境与出路
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作者 蒙柳 帅青 《社会科学动态》 2019年第10期52-55,共4页
修改后的《农村土地承包法》将“三权分置”政策上升为法律制度,确立了土地经营权的融资担保。然而,现行法律关于土地经营权法律性质、抵押物范围界定、抵押主体认定以及抵押配套制度等方面仍缺乏有效支持,因而阻碍了土地经营权抵押的... 修改后的《农村土地承包法》将“三权分置”政策上升为法律制度,确立了土地经营权的融资担保。然而,现行法律关于土地经营权法律性质、抵押物范围界定、抵押主体认定以及抵押配套制度等方面仍缺乏有效支持,因而阻碍了土地经营权抵押的实现。鉴于此,基于“三权分置”视域,审视我国土地经营权抵押的现实背景,剖析土地经营权抵押的法律困境,并提出化解困境的法律建议,就十分重要,也可以促进土地经营权抵押的顺利实现。 展开更多
关键词 三权分置 土地经营权 抵押
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基于二维码的图书馆随书光盘管理新模式研究
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作者 蒙柳 《内蒙古科技与经济》 2021年第19期145-147,共3页
依据随书光盘的特点,分析了图书馆随书光盘的管理现状,对传统的随书光盘管理模式的优缺点进行了论述,通过反思提出了变革的方式;同时研究了基于二维码的图书馆随书光盘管理新模式,希望能够通过应用二维码新技术,来提高读者服务水平。
关键词 图书馆 随书光盘 管理 二维码
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高性能永磁同步发电机无位置传感器控制策略 被引量:1
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作者 刘忠永 国敬 +4 位作者 范涛 边元均 孟柳 章回炫 温旭辉 《兵工学报》 EI CAS CSCD 北大核心 2022年第11期2761-2772,共12页
为提高全电化军用特种车辆的可靠性,进一步提升车载发电系统的功率密度,提出一种全速度范围内的永磁同步发电机无位置传感器控制策略。发电系统采用电压、电流双闭环的矢量控制算法,根据转速划分工作区,在低速区内,通过基于正交锁相环... 为提高全电化军用特种车辆的可靠性,进一步提升车载发电系统的功率密度,提出一种全速度范围内的永磁同步发电机无位置传感器控制策略。发电系统采用电压、电流双闭环的矢量控制算法,根据转速划分工作区,在低速区内,通过基于正交锁相环的角度跟踪器获取转子位置信息,在中高速工作区内,基于线性状态观测器实现转子位置估算,并结合基于递推最小二乘法的参数辨识算法,向观测器实时更新不同工况下的电机参数,以保证无位置算法的鲁棒性。仿真和实验结果表明:该控制策略在全速度范围内皆能实现精准的转子位置观测,电机状态在工作区切换处过渡平滑,负载投切时系统响应快速稳定,保证了特种车辆发电系统运行的可靠性。 展开更多
关键词 永磁同步发电机 无位置传感器 状态观测器 锁相环 参数辨识
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永磁同步电机静止参数辨识及电流环控制器自动参数整定 被引量:9
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作者 孟柳 章回炫 范涛 《兵工学报》 EI CAS CSCD 北大核心 2021年第10期2114-2122,共9页
在永磁同步电机数字控制系统中,电流环控制器的参数整定是影响电流环带宽和系统控制性能的重要因素。为优化控制参数设计流程,提出一种基于静止参数辨识的自动整定方法,使控制系统在匹配不同电机平台时具有通用性。在永磁同步电机静止... 在永磁同步电机数字控制系统中,电流环控制器的参数整定是影响电流环带宽和系统控制性能的重要因素。为优化控制参数设计流程,提出一种基于静止参数辨识的自动整定方法,使控制系统在匹配不同电机平台时具有通用性。在永磁同步电机静止条件下,通过两点式伏安法辨识定子电阻值,消除脉宽调制中死区对定子电阻辨识的影响;通过高频注入法激励定子绕组,运用离散傅里叶变换分别得到交直轴电感值。分析推导自动整定电流环控制器参数方法,并根据辨识参数设计电流环控制器,在两组永磁同步电机实验平台上进行实验。实验结果表明:该控制方法可以使永磁同步电机具有良好的动态和静态性能;永磁同步电机静止参数辨识及电流环控制器参数自动整定方法是有效的。 展开更多
关键词 永磁同步电机 静止参数辨识 电流环控制器 自动参数整定
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基于流动化学平台的3-(2-羟基苯基)-1-(吡啶-3-基)丙-2-烯-1-酮合成实验改进 被引量:2
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作者 王文权 刘萌 +3 位作者 孙康 刘智峰 季晓晖 刘全 《大学化学》 CAS 2022年第7期121-127,共7页
流动化学技术相较于传统间歇式反应,具有高传热与传质效率、高反应安全性、短反应时间以及可精准控制反应参数等优点,从而成为有机合成中最具潜力的技术之一。国外多所高校已经开设流动化学相关课程实验,而我国相关课程实验仍处于起步... 流动化学技术相较于传统间歇式反应,具有高传热与传质效率、高反应安全性、短反应时间以及可精准控制反应参数等优点,从而成为有机合成中最具潜力的技术之一。国外多所高校已经开设流动化学相关课程实验,而我国相关课程实验仍处于起步阶段。本实验将传统有机实验中Claisen-Schmidt反应合成查尔酮衍生物进行改进,通过搭建液相-液相流动化学反应平台进行流动化学合成,并通过紫外-可见光谱仪对反应过程进行监测。该实验在实现相同教学目的下,具有反应时间短、现象明显、碱用量少等显著优势。 展开更多
关键词 流动化学 Claisen-Schmidt反应 查尔酮衍生物 合成
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多焦点人工晶状体植入术后客观视觉质量评估的Meta分析 被引量:3
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作者 刘梦 代诚 李宾中 《国际眼科杂志》 CAS 北大核心 2020年第12期2100-2105,共6页
目的:系统评价多焦点人工晶状体植入术后客观视觉质量的情况。方法:检索PubMed、The Cochrane library、CNKI、Sinomed、迈特思创、万方数据库,检索时限均从建库至2019-12-31。对研究多焦点人工晶状体植入术后客观视觉质量的文献进行Met... 目的:系统评价多焦点人工晶状体植入术后客观视觉质量的情况。方法:检索PubMed、The Cochrane library、CNKI、Sinomed、迈特思创、万方数据库,检索时限均从建库至2019-12-31。对研究多焦点人工晶状体植入术后客观视觉质量的文献进行Meta分析,其中客观视觉质量的评价基于双通道客观视觉质量分析系统(OQASⅡ),包括以下指标:客观散射指数(OSI),调制传递函数截止频率(MTF cut off),斯特列尔比(SR),模拟100%对比度视力(OV100%)、模拟20%对比度视力(OV20%)、模拟9%对比度视力(OV9%)。结果:共有8篇文献纳入研究,共432例567眼。Meta分析结果显示:多焦点人工晶状体与单焦点对照组OSI比较差异有统计学意义[MD=0.66,95%CI(0.42~0.90),P<0.05],而MTF cut off[MD=-1.94,95%CI(-5.58~1.70),P=0.30],SR[MD=0.00,95%CI(-0.02~0.02),P=0.87],OV100%[MD=-0.02,95%CI(-0.14~0.11),P=0.76],OV20%[MD=-0.03,95%CI(-0.14~0.08),P=0.60],OV9%[MD=-0.01,95%CI(-0.09~0.07),P=0.82]差异均无统计学意义。结论:多焦点人工晶状体植入术后客观散射增加可能导致视觉质量下降,其余客观视觉质量参数与单焦点对照组无明显差异。纳入研究均未报道后期随访的情况,由于术后的变化及适应性,多焦点人工晶状体植入术后患者客观视觉质量的远期评估还需要进一步研究。 展开更多
关键词 多焦点人工晶状体 视觉质量 客观视觉质量 客观散射指数 META分析
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基于改进PNN模型的人体健康监测方法 被引量:3
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作者 孟柳 周金治 《自动化仪表》 CAS 2017年第11期1-4,8,共5页
远程人体健康监测分析呈现滞后性、不准确性、设备昂贵等特点,因此难以实现实时、准确的人体健康监测分析。通过对人体健康监测方法和概率神经网络(PNN)的研究,将具有调节参数少、收敛速度快和保证获得贝叶斯最优解等优点的PNN应用于人... 远程人体健康监测分析呈现滞后性、不准确性、设备昂贵等特点,因此难以实现实时、准确的人体健康监测分析。通过对人体健康监测方法和概率神经网络(PNN)的研究,将具有调节参数少、收敛速度快和保证获得贝叶斯最优解等优点的PNN应用于人体健康监测。但是PNN的缺点是未考虑不同类别模型之间的重叠和交错,以及当训练样本不满足假定条件时无法确定是否存在相应的PNN模型。针对这两个缺点,分析了径向基神经网络(RBNN)和广义回归神经网络(GRNN)的网络拓扑结构和优势,创新性地提出在PNN结构的模式层中引入RBNN结构,以及在PNN结构的输出层中引入GRNN结构,得到了一种新的径向基-广义回归-概率混合神经网络(RBF-GR-PMNN),从而满足实时、准确监测人体健康状况的要求。进行了RBF-GR-PMNN与一般PNN的对比试验。试验分别从准确率和运行时间等方面进行对比分析。试验结果证明了改进PNN在这些方面均优于一般PNN,进一步表明了RBF-GR-PMNN模型的有效性。 展开更多
关键词 健康监测 概率神经网络 收敛速度 贝叶斯最优解 网络拓扑 径向基神经网络 广义回归神经网络
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