检索结果-南通市图书馆

Wiener Filtration Algorithm of an Ensemble Pulsar Timescale Based on a Power-law Model of Pulsar Power Spectrum

Research in Astronomy and Astrophysics 2022年第10期22卷 129-140页

作者： Ting-gao Yang Ming-Lei tong yu-Ping gao National Time Service Center Chinese Academy of SciencesXi'an 710600China Key Laboratory of Time and Frequency Primary Standards Chinese Academy of SciencesXi'an 71000China University of Chinese Academy of Sciences Beijing 100049China

An ensemble pulsar timescale derived from the traditional Wiener filtration still contains some high level noise.To improve this situation we developed a Wiener filtration algorithm of the ensemble pulsar timescale based on a power-law model of power spectrum for pulsars.Our algorithm has three strengths:(1)mitigating spectral leakage between frequency bins for Fourier techniques;(2)using a power-law model for power spectrum;(3)signal realization in original residuals of data set by the power-law model.According to improved algorithm we constructed an ensemble pulsar timescale EPT-TAI using timing data with respect to International Atomic Time(TAI)about 16 yr time span of ten pulsars from International Pulsar Timing Array second data release(version A).The results show that EPT-TAI detected correctly the differences TT(BIPM2015)-TAI between terrestrial time TT(BIPM2015)and TAI.Fractional frequency stabilityσzanalysis shows that EPT-TAI does not indicate red noise for 16 yr time interval,and fractional frequency stability for 8 yr and longer time intervals is slightly better than that of TT(BIPM2015)-TAI.Stability for short time intervals of TT(BIPM2015)-TAI is better than that of EPT-TAI,but TT(BIPM2015)-TAI shows red noise for longer time intervals.Using the same algorithm we also derived an ensemble pulsar timescale EPT-TT(BIPM2015)with respect to TT(BIPM2015).The fractional frequency stability curve of EPT-TT(BIPM2015)shows similar characteristics as that of EPT-TAI but with slightly lower values.

关键词： (stars:)pulsars general-time-methods data analysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Single-image night haze removal based on color channel transfer and estimation of spatial variation in atmospheric light

引用

Defence Technology（防务技术） 2023年第7期25卷 134-151页

作者： Shu-yun Liu Qun Hao yu-tong Zhang Feng gao Hai-ping Song yu-tong Jiang Ying-sheng Wang Xiao-ying Cui Kun gao Key Laboratory of Photoelectronic Imaging Technology and System Ministry of EducationSchool of Optics and PhotonicsBeijing Institute of TechnologyBeijing100081China China North Vehicle Research Institute BeijingChina

The visible-light imaging system used in military equipment is often subjected to severe weather conditions, such as fog, haze, and smoke, under complex lighting conditions at night that significantly degrade the acquired images. Currently available image defogging methods are mostly suitable for environments with natural light in the daytime, but the clarity of images captured under complex lighting conditions and spatial changes in the presence of fog at night is not satisfactory. This study proposes an algorithm to remove night fog from single images based on an analysis of the statistical characteristics of images in scenes involving night fog. Color channel transfer is designed to compensate for the high attenuation channel of foggy images acquired at night. The distribution of transmittance is estimated by the deep convolutional network DehazeNet, and the spatial variation of atmospheric light is estimated in a point-by-point manner according to the maximum reflection prior to recover the clear image. The results of experiments show that the proposed method can compensate for the high attenuation channel of foggy images at night, remove the effect of glow from a multi-color and non-uniform ambient source of light, and improve the adaptability and visual effect of the removal of night fog from images compared with the conventional method.

关键词： Dehazing image captured at night Chromaticity fusion correction Color channel transfer Spatial change-based atmospheric light estimation DehazeNet

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Enhancing low-resource cross-lingual summarization from noisy data with fine-grained reinforcement learning

引用

Frontiers of Information Technology & Electronic Engineering 2024年第1期25卷 121-134页

作者： yuxin HUANG Huailing GU Zhengtao yu yumeng gao tong PAN Jialong XU Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming 650504China yunnan Key Laboratory of Artificial Intelligence Kunming University of Science and TechnologyKunming 650504China

Cross-lingual summarization(CLS)is the task of generating a summary in a target language from a document in a source language.Recently,end-to-end CLS models have achieved impressive results using large-scale,high-quality datasets typically constructed by translating monolingual summary corpora into CLS corpora.However,due to the limited performance of low-resource language translation models,translation noise can seriously degrade the performance of these models.In this paper,we propose a fine-grained reinforcement learning approach to address low-resource CLS based on noisy data.We introduce the source language summary as a gold signal to alleviate the impact of the translated noisy target summary.Specifically,we design a reinforcement reward by calculating the word correlation and word missing degree between the source language summary and the generated target language summary,and combine it with cross-entropy loss to optimize the CLS model.To validate the performance of our proposed model,we construct Chinese-Vietnamese and Vietnamese-Chinese CLS datasets.Experimental results show that our proposed model outperforms the baselines in terms of both the ROUGE score and BERTScore.

关键词： Cross-lingual summarization Low-resource language Noisy data Fine-grained reinforcement learning Word correlation Word missing degree

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Surfactant Mediated Microphase Separation in Miscible Block Copolymer of Poly(4-vinyl pyridine-b-hydroxybutylacrylate)

引用

Chinese Journal of Polymer Science 2023年第6期41卷 897-904,I0007页

作者： Xiang-yun Xu Yu-Tong Gao Ying-Ying Wang You-Shuang Zhou Bi-Jin Xiong Jin-Tao Zhu Key Laboratory of Materials Chemistry for Energy Conversion and Storage(HUST)of Ministry of Education School of Chemistry and Chemical Engineering.Huazhong University of Science and Technology(HUST)Wuhan 430074China Key Laboratory of Optoelectronic Chemical Materials and Devices(Ministry of Education) Jianghan UniversityWuhan 430056China Key Laboratory of Green Preparation and Application of Functional Materials(Ministry of Education) Hubei Key Laboratory of Polymer MaterialsFaculty of Materials Science and EngineeringHubei UniversityWuhan 430062China

Miscible disordered block copolymers(BCPs)are rarely studied due to the limits in self-assembly into ordered microstructures.Herein,we proposed a facile method for the transformation of disordered miscible BCPs to comb-like BCPs with well-ordered microphase separation structures via blending with amphiphilic surfactants.In this work,poly(4-vinyl pyridine-b-hydroxybutylacrylate)(P4VP-b-P4HBA)was applied as a model of miscible disordered BCPs and the microphase separation was induced via blending with surfactants of dodecylbenzene sulfonic acid(DBSA)and 3-pentadecylphenol(PDP).The ordered microstructures including spherical and cylindrical morphologies were confirmed by transmission electron microscopy(TEM)and small angle X-ray scattering(SAXS)investigation.These ordered microstructures thermal sensitive,in which ordered and disordered transformation(ODT)was observed in the blend of P4VP-b-P4HBA and PDP whereas it disappeared in the blend of P4VP-b-P4HBA and DBSA.The results show that the thermal stability of the ordered microstructures are strongly depends on the interactions between the miscible BCPs and surfactants,which investigated by in situ SAXS and Fourier transform infrared spectrometer(FTIR).The combination of miscible BCPs and surfactant creates a feasible strategy to fabricate ordered nanostructures,which could be employed to develop complicated nanomaterials.

关键词： ordered disordered vinyl

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Application of machine learning method in optical molecular imaging: a review

引用

Science China(Information Sciences) 2020年第1期63卷 5-20页

作者： yu AN Hui MENG yuan gao tong tong Chong ZHANG Kun WANG Jie TIAN CAS Key Laboratory of Molecular Imaging Beijing Key Laboratory of Molecular ImagingThe State Key Laboratory of Management and Control for Complex SystemsInstitute of Automation Chinese Academy of Sciences Beijing Advanced Innovation Center for Big Data-Based Precision Medicine School of MedicineBeihang University University of Chinese Academy of Sciences

Optical molecular imaging(OMI) is an imaging technology that uses an optical signal, such as near-infrared light, to detect biological tissue in organisms. Because of its specific and sensitive imaging performance, it is applied in both preclinical research and clinical surgery. However, it requires heavy data analysis and a complex mathematical model of tomographic imaging. In recent years, machine learning(ML)-based artificial intelligence has been used in different fields because of its ability to perform powerful data processing. Its analytical capability for processing complex and large data provides a feasible scheme for the requirement of OMI. In this paper, we review ML-based methods applied in different OMI modalities.

关键词： optical molecular imaging machine learning artificial intelligence

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Selective depression action of taurine in flotation separation of specularite and chlorite

引用

International Journal of Mining Science and Technology 2022年第3期32卷 637-644页

作者： Mingyang Li Cheng Yang Zhaoyang Wu Xiangpeng gao Xiong tong Xiankun yu Hongming Long School of Metallurgical Engineering Anhui University of TechnologyMaanshan 243032China Faculty of Land and Resource Engineering Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of Safety and Health for Metal Mine Maanshan 243071China Huawei National Engineering Technical Research Center of High Efficient Recylic Utilization for Metal Minerals Co. LtdMaanshan 243071China

Chlorite,as the most representative gangue mineral associated with specularite,of which the separation of these two minerals is difficult.This paper investigated the depression effect of taurine on specularite/chlorite separation via flotation experiments,adsorption tests,contact angle measurements,Zeta potential detection,FT-IR measurements,and XPS analyses.The results of single mineral flotation indicated that chlorite could be depressed selectively by taurine with the recovery of less than 30%,but the floatability of specularite remains high with recovery rate of 81.77%at pH 10.The artificial mixed mineral flotation results confirmed the effectiveness of taurine as a depressant.Surface adsorption,contact angle,and Zeta potential detection revealed taurine primarily adsorbs on the chlorite surface,which hampered the DDA’s subsequent adsorption and results in the chlorite’s poor floatability.The FT-IR spectra and XPS analyses provided further proof that taurine adsorbed on chlorite surface as an electron donor,and part of the electrons transferred from the sulfonic acid group of taurine to metal ions during the adsorption process.In addition,the hydrogen bond between amino-group of taurine and O ions in chlorite surface was also formed in the adsorption process.Finally,optimized adsorption configurations of taurine on chlorite surfaces were proposed.

关键词： Flotation Taurine Specularite Chlorite Iron-containing Silicates Depressant

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Projections from the Prefrontal Cortex to Zona Incerta Mediate Fear Generalization

引用

Neuroscience Bulletin 2023年第7期39卷 1151-1156页

作者： Kun tong Guang-Kai Bu Si-Qi Jing tong Wu yu-tong Song yue You Le Liu yuan-Hao Chen Jing-Ru Hao Nan Sun Can gao NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic Drugs Jiangsu Province Key Laboratory of AnesthesiologyJiangsu Province Key Laboratory of Anesthesia and Analgesia ApplicationXuzhou Medical UniversityXuzhou 221004China Jiangsu Province Key Laboratory of Brain Disease and Bioinformation Research Center for Biochemistry and Molecular BiologyXuzhou Medical UniversityXuzhou 221004China Department of Anesthesia The Afliated Hospital of Xuzhou Medical UniversityXuzhou 221002China School of Life Sciences Xuzhou Medical UniversityXuzhou 221004China

Dear Editor,Depending on the perceived threat in the environment,organisms can express a broad spectrum of behaviors,ranging from exploration to defensive behaviors[1,2],such as fear response and avoidance.Generalization of fear memory can generate anxiety-related disorders that afflict 10%-30%of individuals worldwide,especially during the epidemic situation[3,4].

关键词： Cortex spectrum genera

来源：

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

Heterologous Expression of Camellia sinensis Late Embryogenesis Abundant Protein Gene 1(CsLEA1)Confers Cold Stress Tolerance in Escherichia coli and Yeast

引用

Horticultural Plant Journal 2021年第1期7卷 89-96页

作者： tong gao yunxin Mo Huiyu Huang Jinming yu Yi Wang Weidong Wang College of Horticulture Northwest A&F UniversityYanglingShaanxi 712100China

Late embryogenesis abundant(LEA)proteins play an important role in plant growth and development,as well as in the plant response to various abiotic stresses.In this study,CsLEA1,a novel gene encoding a LEA_3 subfamily protein,was successfully cloned froma tea plant[Camellia sinensis(L.)O.Kuntze].Bioinformatics analysis and prokaryotic expression assays showed that CsLEA1 is a typical hydrophilic protein with a molecular weight of approximately 10.4 kD.Expression analyses revealed that the transcription of CsLEA1 in C.sinensis leaves was significantly induced by cold stress.In addition,the heterologous expression of CsLEA1 increased the tolerance of Escherichia coli and yeast to cold stress,which might be closely related to the low molecular weight and high hydrophilicity of the CsLEA1.Taken together,our results suggest that CsLEA1 might have an important function in the tolerance of C.sinensis to cold stress,thus providing a potential application in molecular breeding to enhance the cold stress tolerance of tea plants.

关键词： tea plant CsLEA1 heterologous expression cold stress tolerance

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Spheroids of Endothelial Cells and Vascular Smooth Muscle Cells Promote Cell Migration in Hyaluronic Acid and Fibrinogen Composite Hydrogels

引用

Research 2020年第1期2020卷 1673-1687页

作者： Xingang Zuo Haolan Zhang tong Zhou Yiyuan Duan Hao Shou Shan yu Changyou gao MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China Dr.Li Dak Sum&Yip Yio Chin Center for Stem Cell and Regenerative Medicine Zhejiang UniversityHangzhou 310058China

Cell migration plays a pivotal role in many pathological and physiological processes.So far,most of the studies have been focused on 2-dimensional cell adhesion and migration.Herein,the migration behaviors of cell spheroids in 3D hydrogels obtained by polymerization of methacrylated hyaluronic acid(HA-MA)and fibrinogen(Fg)with different ratios were studied.The Fg could be released to the medium gradually along with time prolongation,achieving the dynamic change of hydrogel structures and properties.Three types of cell spheroids,i.e.,endothelial cell(EC),smooth muscle cell(SMC),and EC-SMC spheroids,were prepared with 10,000 cells in each,whose diameters were about 343,108,and 224μm,respectively.The composite hydrogels with an intermediate ratio of Fg allowed the fastest 3D migration of cell spheroids.The ECs-SMCs migrated longest up to 3200μm at day 14,whereas the SMC spheroids migrated slowest with a distance of only~400μm at the same period of time.The addition of free RGD or anti-CD44 could significantly reduce the migration distance,revealing that the cell-substrate interactions take the major roles and the migration is mesenchymal dependent.Moreover,addition of anti-N-cadherin and MMP inhibitors also slowed down the migration rate,demonstrating that the degradation of hydrogels and cell-cell interactions are also largely involved in the cell migration.RT-PCR measurement showed that expression of genes related to cell adhesion and antiapoptosis,and angiogenesis was all upregulated in the EC-SMC spheroids than single EC or SMC spheroids,suggesting that the use of composite cell spheroids is more promising to promote cell-substrate interactions and maintenance of cell functions.

关键词： migration. migrate migration

来源：

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

Schroth exercises improve health-related quality of life and radiographic parameters in adolescent idiopathic scoliosis patients

引用

Chinese Medical Journal 2021年第21期134卷 2589-2596页

作者： Ang gao Jun-yu Li Rui Shao tong-Xuan Wu Yong-Qiang Wang Xiao-Guang Liu Miao yu Department of Orthopaedics Peking University Third HospitalBeijing 100191China department of Rehabilitation Medicine Peking University Third HospitalBeijing 100191China

Background:Finding an optimal treatment strategy for adolescent idiopathic scoliosis(AIS)patients remains challenging because of its intrinsic complexity.For mild to moderate scoliosis patients with lower skeletal growth potential(Risser 3-5),most clinicians agree with observation treatment;however,the curve progression that occurs during puberty,the adolescent period,and even in adulthood,remains a challenging issue for clinicians.The aim of the study is to investigate the efficacy of Schroth exercise in AIS patients with lower skeletal growth potential(Risser 3-5)and moderate scoliosis(Cobb angle 20°-40°).Methods:From 2015 to 2017,data of 64 patients diagnosed with AIS in Peking University Third Hospital were reviewed.Forty-three patients underwent Schroth exercise were classified as Schroth group,and 21 patients underwent observation were classified as observation group.Outcomes were measured by health-related quality of life(HRQOL)and radiographic parameters.HRQOL was assessed using the visual analog scale(VAS)scores for back,Scoliosis Research Society-22(SRS-22)patient questionnaire.Radiographic spinopelvic parameters were obtained from anteroposterior and lateral X-rays.The pre-treatment and post-treatment HRQOL and radiographic parameters were tested to validate Schroth exercise efficacy.The inter-rater reliability of the radiographic parameters was tested using the interclass correlation coefficient(ICC).The pairedt test was used to examine HRQOL and radiographic parameters.Clinical relevance between C2-C7 sagittal vertical axis(SVA)and thoracic kyphosis was analyzed using Spearman correlation.Results:In Schroth group,VAS back score,SRS-22 pain,and SRS-22 self-image domain were significantly improved from pre-treatment 3.0±0.8,3.6±0.5,and 3.5±0.7 to post-treatment 1.6±0.6(t=5.578,P=0.013),4.0±0.3(t=-3.918,P=0.001),and 3.7±0.4(t=-6.468,P<0.001),respectively.No significant improvements of SRS-22 function domain(t=-2.825,P=0.088)and mental health domain(t=-3.174,P=0.061)were observed.The mean Cobb angle decr

关键词： Adolescent idiopathic scoliosis Schroth exercises Health-related quality of life Curve progression Cervical alignment

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：