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A Large Chinese Text Dataset in the Wild

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Journal of Computer Science & Technology 2019年第3期34卷 509-521页

作者： Tai-Ling Yuan zhe Zhu kun Xu Cheng-Jun Li Tai-Jiang Mu Shi-Min Hu Department of Computer Science and Technology Tsinghua UniversityBeijing 100084China Department of Radiology Duke UniversityNorth Carolina 27708U.S.A. Tencent Technology(Beijing)Co.Ltd. Beijing 100080China

In this paper,we introduce a very large Chinese text dataset,in the *** optical character recognition(OCR)in document images is well studied and many commercial tools are available,the detection and recognition of text in natural images is still a challenging problem,especially for some more complicated character sets such as Chinese *** of training data has always been a problem,especially for deep learning methods which require massive training *** this paper,we provide details of a newly created dataset of Chinese text with about 1 million Chinese characters from 3850 unique ones annotated by experts in over 30 000 street view *** is a challenging dataset with good diversity containing planar text,raised text,text under poor illumination,distant text,partially occluded text,*** each character,the annotation includes its underlying character,bounding box,and six *** attributes indicate the charactcr's background complexity,appearance,style,*** the dataset,we give baseline results using state-of-the-art methods for tliree tasks:character recognition(top-1 accuracy of 80.5%),character detection(AP of 70.9%),and text line detection(AED of 22.1).The dataset,source code,and trained models are publicly available.

关键词： Chinese text dataset Chinese text detection Chinese text recognition

Critical thresholds for stage division of water erosion process in different ridge systems in mollisol region of Northeast China

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Journal of Mountain Science 2023年第6期20卷 1540-1560页

作者： JIAO Jian QIN Wei LI kun-heng XU Hai-chao YIN zhe HOU Shu-yan State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing 100038China Research Center on Soil and Water Conservation of the Ministry of Water Resources Beijing 100048China School of Soil and Water Conservation Beijing Forestry UniversityBeijing 100083China Heilongjiang Province Hydropower Research Institute Harbin 150070China

Extreme rainfall events on a slope under ridge tillage systems cause concentrated stream soil *** analyse the critical thresholds for different stages of water erosion process of ridge systems,simulated rainfall-erosion experiments for the contour wide ridge(CWR),contour narrow ridge(CNR),longitudinal wide ridge(LWR),and longitudinal narrow ridge(LNR)were conducted under four rainfall intensities,with slope gradients of 3°and 5°.For the runoff event,the runoff depth order was LNR>LWR>CWR>CNR;the soil loss order was CNR>LNR>CWR>*** product of slope factor(S)and rainfall erosivity(R)or runoff depth(D),can be adopted as critical thresholds for different stages of runoff and soil erosion *** the longitudinal ridge systems,R values were provided for LWR and LNR and were the beginning of sheet flow,whereas the product of rainfall erosivity and slope factor(RS)values were provided for LWR and LNR as the beginning of the accelerated concentrated *** the contour ridge systems,R values were provided for CWR and CNR as critical thresholds for the beginning of *** product of runoff depth and slope factor(DS)values were 9.98 and 7.73 mm for CWR and CNR,respectively,and were critical thresholds for the beginning of ridge failure;the DS values were 18.45 and 12.75 mm for CWR and CNR,respectively,and were critical thresholds for the beginning of the formation of ephemeral gully *** critical thresholds can distinguish different stages of soil erosion process modelling.

关键词： Runoff Soil loss Threshold Ridge failure Artificial rainfall simulation

2023年12月2日菲律宾棉兰老岛附近海域7.6级地震的快速产出参数

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地震科学进展 2024年第2期54卷 168-174页

作者：王永哲张旭张喆陈鲲刘瑞丰中国地震局地球物理研究所北京100081

北京时间2023年12月2日22时37分在菲律宾棉兰老岛(Mindanao)东部海域发生7.6级地震。中国地震局地球物理研究所在震后启动快速响应,组织相关领域研究人员对此次地震的震源参数、震源机制、破裂过程和地震辐射能量等进行了估计,基于震源... 详细信息

北京时间2023年12月2日22时37分在菲律宾棉兰老岛(Mindanao)东部海域发生7.6级地震。中国地震局地球物理研究所在震后启动快速响应,组织相关领域研究人员对此次地震的震源参数、震源机制、破裂过程和地震辐射能量等进行了估计,基于震源模型进行了震动图模拟、同震形变场模拟。结果表明,此次地震发生在菲律宾海板块与欧亚板块/巽他地块碰撞的俯冲带板片上,以逆冲机制为主,能量集中在前约40 s内释放,断层破裂最大滑动量达到7 m;震源辐射地震能量的效率偏低,慢度系数略低于全球平均水平,与同样矩震级大小的地震相比,震感不强烈;极震区震动烈度可能达Ⅸ度以上,可能的受灾范围近27000 km^(2);此次地震引起了显著的同震位移,最大水平向位移达到0.6 m、垂直向位移达到1.2 m。综合分析可知,此次地震不会产生大规模海啸。

关键词：菲律宾棉兰老岛地震震源参数破裂过程震动图预测同震形变场模拟地震辐射能量 InSAR 三维形变

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光纤光栅技术在天然气管道安全监测中的研究进展

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管道技术与设备 2024年第1期 27-33,42页

作者：田野赵敏李坤杨光王晓航刘哲国家管网集团西部管道有限责任公司北京声创新技术发展有限责任公司

基于光纤光栅的管道安全监测技术具有本质安全和无电磁干扰等优点,适用于易燃易爆环境。文中介绍了光纤布拉格光栅(FBG)的技术现状,对不同安装方式的FBG传感器实现原理、主要参数及性能特点进行了对比分析,介绍了超弱光纤光栅传感阵列... 详细信息

基于光纤光栅的管道安全监测技术具有本质安全和无电磁干扰等优点,适用于易燃易爆环境。文中介绍了光纤布拉格光栅(FBG)的技术现状,对不同安装方式的FBG传感器实现原理、主要参数及性能特点进行了对比分析,介绍了超弱光纤光栅传感阵列的技术优势和应用场景,提出了基于FBG传感的管道安全监测技术研究难点和发展方向,为构建天然气管道安全监测技术体系提供参考。

关键词：天然气管道安全监测光纤传感光纤布拉格光栅

Characterization of Acidic Glycosphingolipid Changes in C6 Glioma Rats Treated With Temozolomide Using Ultra-High-Performance Liquid Chromatography Coupled With Quadrupole Time-of-Flight Mass Spectrometry

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Journal of Analysis and Testing 2020年第3期4卷 217-225页

作者： Tian-kun Ren Meng-Lin Li Hao zheng zhe Wang Jin-Lan Zhang State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaPeking Union Medical College and Chinese Academy of Medical SciencesBeijing 100050People’s Republic of China

Ganglioside and sulfatide are primary components of acidic glycosphingolipids(AGSLs),which are abundant in the brain *** are potential tumor *** this paper,we use ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry to generate a first-ever comprehensive profile of AGSLs in brain and plasma of C6 glioma rats treated with temozolomide(TMZ).The AGSLs detected consisted mainly of C18-/C20-sphingosine.12,20,19,14 and 12 species were identified in GM1,GD1a,GD1b,GM3 and GT1b ganglioside groups which were abundant in rat brain,*** five groups accounted for 88-89%of total ganglioside ***,no AGSLs were detected in rat *** biomarkers for abnormal changes in the glioma model and the protective effect of TMZ were mainly found in these ganglioside groups and *** main lipid component of central and peripheral nervous system myelin sheathes is sulfatide,which is upregulated in many *** properties of TMZ are due to modulation of sulfatide levels in tumor tissues.

关键词： Acidic glycosphingolipids Temozolomide C6 glioma UPLC-QTOF-MS

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水利工程微波通信技术问题研究及优化策略

通信电源技术 2024年第18期41卷 158-160页

作者：王哲刘玉敏郭舒琨俞蕾陈堃安徽省引江济淮集团有限公司安徽合肥230000

微波通信技术作为重要的信息传输手段,在水利工程监控、调度等方面发挥着重要作用。然而,该技术在实际应用中面临着信号衰减、电磁干扰与多径效应、环境因素的影响以及设备老化与维护等问题。为解决这些问题,需要采取一系列优化策略,包... 详细信息

微波通信技术作为重要的信息传输手段,在水利工程监控、调度等方面发挥着重要作用。然而,该技术在实际应用中面临着信号衰减、电磁干扰与多径效应、环境因素的影响以及设备老化与维护等问题。为解决这些问题,需要采取一系列优化策略,包括提升信号传输质量、抑制电磁干扰与多径效应、增强通信系统对环境变化的适应能力以及加强设备维护与更新等。这些策略的实施有助于提高水利工程中微波通信技术的稳定性和可靠性,为水利通信的可持续发展提供有力支持。

关键词：微波通信信号衰减电磁干扰通信网络优化

三株传染性法氏囊病病毒重组毒株的致病性研究

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畜牧兽医学报 2024年第6期55卷 2550-2559页

作者：杨坤马静文周新瑞罗烈柱刘喆胡自强武星辰梁立滨高诗敏山西农业大学动物医学学院太谷030801

鸡传染性法氏囊病(IBD)是由传染性法氏囊病毒(IBDV)引起雏鸡发病的一种高致病性免疫抑制性疾病,目前IBDV重组变异株性对鸡养殖业有严重危害。本研究对三株IBDV重组毒株进行全基因序列分析并测定其致病性差异。通过鸡胚分离鉴定并增殖三... 详细信息

鸡传染性法氏囊病(IBD)是由传染性法氏囊病毒(IBDV)引起雏鸡发病的一种高致病性免疫抑制性疾病,目前IBDV重组变异株性对鸡养殖业有严重危害。本研究对三株IBDV重组毒株进行全基因序列分析并测定其致病性差异。通过鸡胚分离鉴定并增殖三株IBDV毒株,利用Mega 11、MegAlign软件与参考毒株进行核苷酸同源性比对和氨基酸进化树绘制,将病原感染SPF鸡测定致病性,用实时荧光定量PCR方法检测脏器病毒拷贝量,结果显示:GD-1株属于A2dB3型,呈现新型变异A超强B特点,GD-2株和GD-3株同属于A3B1型,分别呈现超强A新型变异B和超强A早期变异B特点;三株病毒均未引起雏鸡死亡,GD-1株无明显临床症状,GD-2株和GD-3株在攻毒后7 d出现精神沉郁,卧地不起;引起其法氏囊显著萎缩、脾肿大,法氏囊载毒量要高于脾载毒量,在攻毒后第14天时GD-1株的法氏囊载毒量显著高于GD-2株和GD-3株;三组试验鸡法氏囊滤泡均发生萎缩,且GD-2组和GD-3组病变更严重,脾则是GD-1组病变更严重。本研究测定三株IBDV的序列、绘制进化树,测定致病性,显示三株病毒都有新型变异株的变异趋势,为研究IBDV致病机理和防控IBD提供参考。

关键词：传染性法氏囊病毒序列分析重组病毒致病性

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Low generational polyamidoamine dendrimers to enhance the solubility of folic acid:A‘‘dendritic effect’’investigation

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Chinese Chemical Letters 2014年第5期25卷 815-818页

作者： Yong Zhang Mei-Ying Xu Tie-kun Jiang Wei-zhe Huang Jiang-Yu Wu School of Material Sciences & Engineering Wuhan Institute of Technology

Low generational（G0–G2,G for generation） polyamidoamine（PAMAM） dendrimers were investigated as enhancers to improve the aqueous solubility of folic acid at pH 11 and pH *** these two cases,the solubility of folic acid increases with both the dendrimer concentration and ***,the solubilization mechanism is *** electrostatic interaction between the primary amines of dendrimers and the ionized carboxylic groups of folic acid dominates the dissolution process at pH 11 while the increase of the solubility of folic acid at pH 5 is attributed to the hydrophobic encapsulation inside the dendrimer *** addition,for comparison ethylenediamine was used as a small molecule control to examine the ‘‘dendritic effect＇＇ in the dendrimer-related solubilization ***,PAMAM dendrimers exhibit,at pH 5,a significant superiority over ethylenediamine in enhancing solubility,whereas this ‘‘dendritic effect＇＇ cannot be observed under the basic condition.

关键词： Polyamidoamine Dendrimer Folic acid Electrostatic interaction Hydrophobic encapsulation

Improvement of a continuous-variable measurement-device-independent quantum key distribution system via quantum scissors

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Chinese Physics B 2022年第9期31卷 202-207页

作者： Lingzhi Kong Weiqi Liu Fan Jing zhe-kun Zhang Jin Qi Chen He College of Information Science and Technology Northwest UniversityXi'an 710127China

We propose a new scheme to enhance the performance of the Gussian-modulated coherent-state continuous-variable measurement-device-independent quantum key distribution(CV-MDI-QKD)system via quantum scissors(QS)operation at Bob's *** an non-deterministic amplifying setup,we firstly introduce the QS-enhanced CV-MDI-QKD protocol and then investigate the success probability of the QS operation in accordance with the equivalent one-way ***,we investigate the effect of the QS operation on the proposed scheme and analyze the performance of the QS-enhanced CV-MDI-QKD system under the extreme asymmetric *** results show that the QS operation can indeed improve the performance of the CV-MDI-QKD system ***-enhanced CV-MDI-QKD protocol outperforms the original CV-MDI-QKD protocol in both the maximum transmission distance and the secret key ***,the better the performance of QS operation,the more significant the improvement of performance of the system.

关键词： measurement-device-independent quantum key distribution quantum scissors performance