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一种基于快速图像去模糊的视觉室内定位方法

信息技术与信息化 2024年第4期 15-19页

作者：吕梦妍郭新新张坤鹏张立晔山东理工大学计算机科学与技术学院山东淄博255000

在图像拍摄过程中,相机抖动、物体运动等因素导致图像产生模糊,进而使得模糊图像的特征点减少、匹配效果较差,最终对室内定位精度产生负面影响。为解决这一问题,提出一种基于快速图像模糊识别和模糊去除的视觉室内定位方法。首先,采用... 详细信息

在图像拍摄过程中,相机抖动、物体运动等因素导致图像产生模糊,进而使得模糊图像的特征点减少、匹配效果较差,最终对室内定位精度产生负面影响。为解决这一问题,提出一种基于快速图像模糊识别和模糊去除的视觉室内定位方法。首先,采用编解码器结构学习上下文信息,随后与高分辨率分支结合以保留空间细节,最终生成高质量的清晰的图像,消除图像模糊对定位精度的影响。接着,通过图像检索、特征点提取和匹配的方式计算查询相机的位置。实验结果表明,所提出的方法在GoPro数据集上峰值信噪比(PSNR)为31.64,结构相似性指数(SSIM)为0.949,平均去模糊处理时间为24ms;去模糊处理后,85%的室内查询图片定位误差小于0.5m。基于快速图像去模糊的视觉室内定位方法能够有效恢复图像细节,提高室内视觉定位的精度。

关键词：视觉定位图像去模糊图像检索五点法室内定位位置估计

不同土壤水分处理对长白山区仿生栽培茖葱生物量与营养品质的影响

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吉林林业科技 2022年第3期51卷 1-4,12页

作者：刘佳艺徐光花冯博李成龙马思佳吕梦燕长春市净月设计集团有限公司吉林长春130118 吉林省林业科学研究院吉林长春130033 长春市净月潭实验林场吉林长春130118 长春净月高新技术产业开发区净月南环小学吉林长春130118

本研究以敦化地区仿生栽培茖葱为试材,探究了土壤水分状况与其生长及营养物质积累的关系。结果表明:土壤水分状况对茖葱生物量与营养物质积累的影响较显著,轻度水分胁迫(土壤含水量为田间持水量的70%)对营养生长期的各部分生物量积累有... 详细信息

本研究以敦化地区仿生栽培茖葱为试材,探究了土壤水分状况与其生长及营养物质积累的关系。结果表明:土壤水分状况对茖葱生物量与营养物质积累的影响较显著,轻度水分胁迫(土壤含水量为田间持水量的70%)对营养生长期的各部分生物量积累有明显的促进作用,同时也促进了展叶盛期的营养物质积累,其维生素C、总黄酮、β-胡萝卜素、可溶性糖与可溶性蛋白含量分别比对照组高8.3%、6.0%、18.0%、14.0%与8.6%,为最有利生长与营养物质积累的土壤水分处理。因此,应注意水分调控,使营养生长期的土壤含水量保持在田间持水量的70%左右,以促进茖葱的生长,并改善营养品质。

关键词：茖葱水分处理生物量营养品质

PCI术前应用替罗非班对急性心肌梗死患者微血管阻塞和左心室功能的影响

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中国实用医刊 2021年第19期48卷 110-114页

作者：史志明张丽霞张静冯炎青张晋峰吕孟妍山西省临汾市中心医院心血管内科 041000

目的探讨PCI术前应用替罗非班对急性心肌梗死(AMI)患者微血管阻塞和左心室功能的影响。方法抽取2019年9月至2020年9月临汾市中心医院收治的92例AMI患者,按照随机数字表法将其分为观察组和对照组,每组46例。两组AMI患者均行经皮冠状动脉... 详细信息

目的探讨PCI术前应用替罗非班对急性心肌梗死(AMI)患者微血管阻塞和左心室功能的影响。方法抽取2019年9月至2020年9月临汾市中心医院收治的92例AMI患者,按照随机数字表法将其分为观察组和对照组,每组46例。两组AMI患者均行经皮冠状动脉介入治疗(PCI),观察组在PCI术前采用替罗非班治疗,分析替罗非班对患者微血管阻塞及左心室功能的影响。结果治疗后,两组QT间期离散度(QTd)较治疗前降低,峰值强度(PI)、曲线下面积(AUC)较治疗前升高,且观察组QTd低于对照组,PI、AUC高于对照组(P<0.05)。治疗后,观察组ST段降低幅度高于对照组,酶峰时间低于对照组(P<0.05)。与治疗前比较,治疗后两组活化部分凝血活酶时间(APTT)、凝血酶原时间(PT)、凝血酶时间(TT)、D二聚体(D-D)水平均升高,纤维蛋白原含量(FIB)降低(P<0.05);且观察组D-D、APTT、PT、TT高于对照组,FIB低于对照组(P<0.05)。与治疗前比较,治疗后两组左心室射血分数(LVEF)均升高,左心室收缩末期容积(LVESVI)、室壁运动积分指数(WMSI)降低(P<0.05),且观察组LVESVI、WMSI低于对照组,LVEF高于对照组(P<0.05)。与治疗前比较,治疗后两组单核细胞血小板聚集体(MPA)、溶酶体膜糖蛋白(CD63)、血小板α颗粒表面膜糖蛋白(CD62P)均降低(P均<0.05),且观察组MPA、CD63、CD62均低于对照组(P均<0.05)。结论在AMI患者PCI术前应用替罗非班治疗后,患者微血管循环及凝血功能均得到显著改善,心肌损伤明显降低,心功能恢复较好。

关键词：心肌梗死替罗非班微血管阻塞左心室功能

Single-cell transcriptomics reveals tumor landscape in ovarian carcinosarcoma

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第8期25卷 686-699页

作者： Junfen XU mengyan TU Department of Gynecologic Oncology Women’s HospitalZhejiang University School of MedicineHangzhou 310006China Zhejiang Provincial Clinical Research Center for Obstetrics and Gynecology Hangzhou 310006China

Objective:The present study used single-cell RNA sequencing(scRNA-seq)to characterize the cellular composition of ovarian carcinosarcoma(OCS)and identify its molecular ***:scRNA-seq was performed in resected primary OCS for an in-depth analysis of tumor cells and the tumor *** staining was used for *** scRNA-seq data of OCS were compared with those of high-grade serous ovarian carcinoma(HGSOC)tumors and other OCS ***:Both malignant epithelial and malignant mesenchymal cells were observed in the OCS patient of this *** identified four epithelial cell subclusters with different biological *** them,epithelial subcluster 4 presented high levels of breast cancer type 1 susceptibility protein homolog(BRCA1)and DNA topoisomerase 2-α(TOP2A)expression and was related to drug resistance and cell *** analyzed the interaction between epithelial and mesenchymal cells and found that fibroblast growth factor(FGF)and pleiotrophin(PTN)signalings were the main pathways contributing to communication between these ***,we compared the malignant epithelial and mesenchymal cells of this OCS tumor with our previous published HGSOC scRNA-seq data and OCS *** the epithelial subclusters in the OCS tumor could be found in the HGSOC ***,the mesenchymal subcluster C14 exhibited specific expression patterns in the OCS tumor,characterized by elevated expression of cytochrome P450 family 24 subfamily A member 1(CYP24A1),collagen type XXIIIα1 chain(COL23A1),cholecystokinin(CCK),bone morphogenetic protein 7(BMP7),PTN,Wnt inhibitory factor 1(WIF1),and insulin-like growth factor 2(IGF2).Moreover,this subcluster showed distinct characteristics when compared with both another previously published OCS tumor and normal ovarian ***:This study provides the single-cell transcriptomics signature of human OCS,which constitutes a new resource for elucidating OCS diversity.

关键词： Ovarian carcinosarcoma Single-cell RNA sequencing(scRNA-seq) Tumor heterogeneity

Reducible solution to a quaternion tensor equation

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Frontiers of Mathematics in China 2020年第5期15卷 1047-1070页

作者： mengyan XIE Qing-Wen WANG Department of Mathematics Shanghai UniversityShanghai 200444China

We establish necessary and sufficient conditions for the existence of the reducible solution to the quaternion tensor equation A*N C*NB=C via Einstein product using Moore-Penrose inverse,and present an expression of the reducible solution to the equation when it is ***,to have a general solution,we give the solvability conditions for the quaternion tensor equation A1*N C1*MB1+a1*C2*MB2+A2*NC3*MB2=e,which plays a key role in investigating the reducible solution to A*NC*NB=*** expression of such a solution is also presented when the consistency conditions are *** addition,we show a numerical example to illustrate this result.

关键词： Quaternion tensor quaternion tensor equation Einstein product Moore-Penrose inverse general solution reducible solution

Influence of the Gaussian colored noise and electromagnetic radiation on the propagation of subthreshold signals in feedforward neural networks

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Science China(Technological Sciences) 2021年第4期64卷 847-857页

作者： GE mengyan WANG GuoWei JIA Ya Department of Physics Central China Normal UniversityWuhan 430079China

Iterative methods are used to simulate the in vitro feedforward neural networks in physiological *** can be propagated to a minimum of ten ***,the discharge activity of each group will be more *** feedforward neural networks have a wide range of applications in machine learning,and the weight of synapses considerably influences the propagation of weak ***,we investigated the effect of Gaussian colored noise and electromagnetic radiation on the propagation of the subthreshold excitatory postsynaptic current signals in the input layer of the multilayer Izhikevich neural feedforward *** the absence of electromagnetic radiation,the excitatory postsynaptic current signal is stably propagated and amplified in multilayer feedforward neural networks under the optimal Gaussian colored noise strength or correlation time in the output layer of the *** with the case in which there is no electromagnetic radiation,the presence of electromagnetic radiation slightly reduces the propagation of weak ***,the time required to propagate the excitatory postsynaptic current signal to the output layer increases with the increasing feedback *** feedforward neural network considered in this study is a considerably simple *** complex structures,such as backward connection and delayed feedback,can be observed in real biological ***,the next step will be to study more complex neural models with neuron models based on the physiological experimental data and compare them with real biological ***,the study of neural networks can be combined with an experimental study about the auditory nervous system of bats to understand the biological mechanism associated with the auditory system function of bats from two perspectives.

关键词： feedforward neural network colored noise electromagnetic radiation signal propagation

Electrochemical Fabrication and Electrocatalytic Properties of Nanostructured Mesoporous Platinum Microelectrodes

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Journal of Materials Science & Technology 2005年第6期21卷 863-865页

作者： mengyan NIE Joanne M.Elliott School of Chemistry The University of Reading Reading RG6 6AD UK

Electrodeposition from a lyotropic liquid crystal template medium was used to produce nanostructured platinum microelectrodes with high specific surface area and high mass transport efficiency. Compared to polished and conventional platinized microelectrodes, well-ordered nanostructured platinum microelectrodes exhibited enhanced electrocatalytic properties for oxygen and ascorbic acid, whilst well-ordered nanostructured platinum microelectrodes offered improved electrocatalytic properties for oxygen reduction compared to disordered nanostructured platinum microelectrodes.

关键词： Liquid crystal template Mesoporous Microelectrode Electrocatalysis

Femtosecond laser irradiation-induced infrared absorption on silicon surfaces

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International Journal of Smart and Nano Materials 2015年第2期6卷 113-123页

作者： Qinghua Zhu mengyan Shen Department of Physics and Applied Physics and Nanomanufacturing CenterUniversity of Massachusetts Lowell1 University AvenueLowellMA 01854USA

The near-infrared(NIR)absorption below band gap energy of crystalline silicon is significantly increased after the silicon is irradiated with femtosecond laser pulses at a simple experimental *** absorption increase in the NIR range primarily depends on the femtosecond laser pulse energy,pulse number,and pulse *** Raman spectroscopy analysis shows that after the laser irradiation,the silicon surface consists of silicon nanostructure and amorphous *** femtosecond laser irradiation leads to the formation of a composite of nanocrystalline,amorphous,and the crystal silicon substrate surface with *** composite has an optical absorption enhancement at visible wavelengths as well as at NIR *** composite may be useful for an NIR detector,for example,for gas sensing because of its large surface area.

关键词： near-infrared absorption nanostructured silicon amorphous silicon

Automatic Scallion Seedling Feeding Mechanism with an Asymmetrical High-order Transmission Gear Train

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Chinese Journal of Mechanical Engineering 2020年第1期33卷 148-161页

作者： Xiong Zhao Jun Ye mengyan Chu Li Dai Jianneng Chen Faculty of Mechanical Engineering and Automation Zhejiang Sci-Tech UniversityHangzhou 310018China Key Laboratory of Zhejiang Transplanting Equipment Technology Zhejiang Sci-Tech UniversityHangzhou 310018China

The current automatic scallion-transplanting machine is a complicated mechanism composed of two linkage mechanisms and two band *** delivers seedlings ine ciently because of the movement limitations of the linkage *** paper proposes a new high-order non-circular gear train for an automatic scallion-seedling feeding *** proposed gear train has an asymmetrical transmission ratio;i.e.,its transmission ratio *** allows the mechanism’s execution component to move in a long displacement and rotate in a large rotation *** long displacement enables the execution component to reach the designed working position,and the large rotation angle allows it to feed a scallion in the required pose.A mathematical model for calculating the asymmetrical transmission ratio was established according to the closure requirements and the full-cycle motion of the driven gear pitch ***,the parameter-design model of the new seedling-feeding mechanism was established,based on precise pose points and trajectory-shape control ***,an aided-design program was developed to obtain the parameter-solution domain of the scallion-seedling feeding *** mechanism parameters,which met the seedling-feeding function,were optimized to determine the transmission ratio,using a program and a kinematic ***,a prototype of the mechanism was produced,and a seedling-feeding experiment was carried ***-thousand seedlings were tested at a rate of 100 seedlings per minute,and the statistical success rate was 93.4%.Thus,the automatic scallion-seedling feeding mechanism significantly improves the e ciency of automatically transplanting scallions.

关键词： Asymmetric transmission Scallion transplanting High-order gear Non-circular gear Planetary gear train