检索结果-南通市图书馆

Detection method of absence seizures based on Resnet and bidirectional GRU

Acta Epileptologica 2023年第1期6卷 34-42页

作者： Lijun Li Hengxing Zhang Xiaomei Liu Jie Li Lei Li Dan Liu Jieqing Min Ping Zhu Huan Xia Shangkun Wang Li Wang Kunming children‘s hospital Kunming 650000China zhengzhou zoneyet technology corp. LtdZhengzhou 450000China

Background Epilepsy is a common chronic neurological *** repeated seizure attacks have a great negative impact on patients’physical and mental *** diagnosis of epilepsy mainly depends on electroencephalogram(EEG)signals detection and *** are two main EEG signals detection methods for *** is the detection based on abnormal waveform,the other is the analysis of EEG signals based on the traditional machine *** feature extraction method of the traditional machine learning is difcult to capture the high-dimension information between adjacent *** In this paper,redundant information was removed from the data by Gaussian fltering,downsampling,and short-time Fourier *** Neural Networks(CNN)was used to extract the high-dimensional features of the preprocessed data,and then Gate Recurrent Unit(GRU)was used to combine the sequence information before and after,to fully integrate the adjacent information EEG signals and improve the accuracy of the model *** Four models were designed and *** experimental results showed that the prediction model based on deep residual network and bidirectional GRU had the best efect,and the test accuracy of the absence epilepsy test set reached 92%.Conclusions The prediction time of the network is only 10 sec when predicting four-hour EEG *** can be efectively used in EEG software to provide reference for doctors in EEG analysis and save doctors’time,which has great practical value.

关键词： Resnet Epilepsy GRU Electroencephalogram

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

Microstructural Characteristics and Stability in a RapidlySolidified Al-Fe-Nb-Si Alloy

引用

Journal of Materials Science & technology 1997年第6期13卷 515-517页

作者： Guan, SK Shen, NF Gong, YL Hu, HQ zhengzhou Univ Technol Dept Mat Sci & Engn Zhengzhou 450002 Peoples R China Cent China Petr & Nat Gas Dev corp.Henan Province Zhengzhou 450002 Peoples R China Univ Sci & Technol Beijing Inst Mat Beijing 100083 Peoples R China

The microstructure and stability in a rapidly solidified Al-Fe-Nb-Si alloy were studied by using transmission electron microscopy (TEM) with energy dispersive X-ray spectrometry (EDXS) and X-ray diffraction technique. It is shown that the addition of Nb to Al-Fe-Si alloy may increase undercooling of melt, and form the featureless zone structure, the size of the intercellular phases and the distance between intercellulars of Al-Fe-Nb-Si alloy are two times smaller than that of AI-Fe-V-Si alloy under the same conditions. Further, the microstructure of the featureless zone has the better thermal stability after annealing at 623 K for 24 h.

关键词： Aluminum alloys

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

Influence of Erosion Induced by NaCl on the Mechanical Performances of Alkali-Activated Mineral Admixtures

引用

Fluid Dynamics & Materials Processing 2023年第9期19卷 2385-2398页

作者： Jing Yu Jie Ren Guangming Shen Weixiang Sun Hui Wang Department of Architectural Engineering Ningbo PolytechnicNingbo315000China technology and Performance Management Department China Construction Infrastructure Corp.Ltd.Beijing10029China Chief Engineer’s Office Jiuzhou Engineering Design Co.Ltd.Zhengzhou451162China School of Civil Engineering and Geographic Environment Ningbo UniversityNingbo315000China

In this paper,the inﬂuence of NaCl freeze-thaw(F-T)cycles and dry-wet(D-W)alternations on theﬂexural,com-pressive and bonding strengths of alkali-activatedﬂy ash(FA)and a blast furnace slag powder(BFS)is *** considered NaCl concentration is 3%.The effect of polypropyleneﬁbers on the mechanical strengths is also *** electron microscopy(SEM),thermogravimetry(TG)and X-ray diffraction(XRD)are selected to discern the mechanisms underpinning the NaCl-induced *** obtained results indicate that the best results in terms of material resistance are obtained with admixtures containing 60%BFS and 40%FA in terms of mass ratio and 3%polypropyleneﬁbers in terms of volume *** maximum rates of decrease of theﬂexural,compressive and bonding strengths after 300 NaCl F-T cycles are 21.5%,20.3%and 22.6%,*** corresponding rates of decrease due to NaCl D-W alternations are 28.1%,26.1%and 31.5%,*** TG curves show that the alkali-activating activity of BFS is higher than that of ***,in theﬁrst case,the microstructure of the hydration products is more *** results also show that NaCl F-T cycles lead to increasing cracks in the alkali-activated BFS.

关键词： Mechanical performances alkali-activated NaCl dry-wet alternations NaCl freeze-thaw cycles microstructure

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

CFD prediction of physical field for multi-air channel pulverized coal burner in rotary kiln

引用

Journal of Central South University of technology 2006年第1期13卷 75-79页

作者：马爱纯周孑民欧俭平李旺兴 School of Energy and Power Engineering Central South University Changsha 410083 China Institute of Light Metal China Aluminum Corp Zhengzhou 450041 China

A 3-D numerical simulation with CFX software on physical field of multi-air channel coal burner in rotary kiln was carried out. The effects of various operational and structural parameters on flame feature and temperature distribution were investigated. A thermal measurement was conducted on a rotary kiln (4.5m in diameter, 90m in length) with four-air channel coal burner to determine the boundary conditions and to verify the simulation results. The calculation result shows that the distribution of velocity near burner exit is saddle-like; recirculation zones near nozzle and wall are useful for mixture primary air with coal and high temperature fume. A little central airflow can avoid coal backing up and cool nozzle. Adjusting the ratio of internal airflow to outer airflow is an effective and major means to regulate flame and temperature distribution in sintering region. Large whirlcone angle can intensify disturbution range at flame root to accelerate ignition and mixture. Large coal size can reduce high temperature region and result in coal combusting insufficiently. Too much combustion air will lengthen flame and increase heat loss.

关键词： CFD numerical simulation CFX physical field multi-air channel coal burner rotary kiln

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

Effect of cyclic wetting-drying on tensile mechanical behavior and microstructure of clay-bearing sandstone

引用

International Journal of Coal Science & technology 2021年第5期8卷 956-968页

作者： Pingye Guo Juan Gu Yi Su Jiong Wang Zhanwen Ding State Key Laboratory for Geo-Mechanics and Deep Underground Engineering Beijing 100083China School of Mechanics Architecture and Civil EngineeringChina University of Mining and TechnologyBeijing 100083China Tang Steel International Engineering technology corp Tangshan 063000China China Henan Geological and Mineral Resources Construction Engineering(Group)Co. LtdZhengzhou 450007China

The understanding of the weakening mechanism of tensile strength of rock subjected to cyclic wetting-drying is critical for rock *** strength tests were conducted on a total of 35 sandstone specimens with different wetting-drying *** crack propagation process and acoustic emission characteristics of the tested samples were obtained through a high-speed camera and acoustic emission *** results indicate that the tensile strength is observably reduced after cyclic wetting-drying,and the extent of the reduction is not only related to the number of wettingdrying cycle,but also closely related to the clay mineral content of the *** addition,as the cycles of wetting-drying increase,the effect of each single cycle on tensile strength get reduced until it becomes ***,the crack initiation and penetration time is prolonged as the number of wetting-drying cycle increases,which indicates that cyclic wetting-drying weakens the rock stiffness and enhances the ductility of ***,the acoustic emission characteristics of the tested samples further confirmed the ductile behaviour of the sandstone samples with increasing wetting-drying ***,through the analysis of the microstructure and mineral composition of the samples with different wetting-drying cycles,it is concluded that the main weakening mechanisms of sandstones containing clay minerals are frictional reduction,chemical and corrosive deterioration.

关键词： Sandstone Wetting-drying cycle Tensile strength Weakening mechanism Failure characteristics

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

Elucidating the effect of oxides on the zeolite catalyzed alkylation of benzene with 1-dodecene

引用

Chinese Journal of Chemical Engineering 2023年第4期56卷 126-135页

作者： Shiyong Xing Yan Cui Tiefeng Wang Jinwei He Minghan Han Beijing Key Laboratory of Green Chemical Reaction Engineering and technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Petrochemical Research Institute PetroChina Company LimitedBeijing 100195China Henan Energy and Chemical Industry Group Company Limited Zhengzhou 450046China

In the present work, the effect of oxides on the alkylation of benzene with 1-dodecene was comprehensively investigated over MCM-49 n-heptanol, n-heptaldehyde and n-heptanoic acid were selected as the model oxides herein, and obvious decrease of lifetime could be caused by only trace amount of oxides added in the feedstocks. However, the deactivated catalysts were difficult to be regenerated by extraction with hot benzene. Additionally, coke-burning was also proved to be incapable to regenerate the deactivated catalysts mainly for the dealumination during calcination. Further characterizations complementary with DFT calculations were conducted to demonstrate that the deactivation was mainly due to the firm adsorption of oxides on the acid sites.

关键词： Zeolite 1-dodecene Alkylation Oxides Deactivation

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

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

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：