检索结果-南通市图书馆

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

DM4过程SQL语言的设计与实现

华中科技大学学报（自然科学版） 2006年第3期34卷 14-16页

作者：谢美意冯玉才华中科技大学计算机科学与技术学院湖北武汉430074

在商用数据库管理系统DM4中设计并实现了过程SQL语言DMPL/SQL.提出了DMPL/SQL语言解释器的总体结构.该解释器由编译器和虚拟机两部分构成.编译器分析源代码并生成中间代码,虚拟机以立即或延迟的方式对中间代码进行解释执行.介绍了实现DM... 详细信息

在商用数据库管理系统DM4中设计并实现了过程SQL语言DMPL/SQL.提出了DMPL/SQL语言解释器的总体结构.该解释器由编译器和虚拟机两部分构成.编译器分析源代码并生成中间代码,虚拟机以立即或延迟的方式对中间代码进行解释执行.介绍了实现DMPL/SQL语言解释器的关键技术.为提高程序的执行效率,在名字解析、SQL语句的执行以及异常处理等阶段采用了多种优化方法.该语言目前已广泛使用于基于DM4的数据库应用中.

关键词：过程SQL语言解释器虚拟机

在线全文

学校读者我要写书评

暂无评论

实时应用的可预测性研究和分析

华中理工大学学报 1999年第4期27卷 18-19页

作者：胡贯荣谢美意华中理工大学计算机科学与技术学院

阐述了实时应用的可预测性概念，以及实时应用的静态特性和动态特性，并从静态可预测性和动态可预测性两个方面分析支持可预测性的主要策略．

关键词：可预测性静态可预测性动态可预测性实时系统

在线全文

学校读者我要写书评

暂无评论

分布式IPC实时性能的研究

华中理工大学学报 1999年第4期27卷 20-21,33页

作者：胡贯荣谢美意华中理工大学计算机科学与技术学院

抽象出分布式实时ＩＰＣ的一致模型，以此模型为基础，从及时性和可预测性两个方面分析了影响其实时性能的主要因素，最后总结出一个分析评价分布式ＩＰＣ实时性能的客观标准。

关键词：分布式实时系统 IPC 可预测性实时性能

在线全文

学校读者我要写书评

暂无评论

分布式实时应用的两个重要问题

计算机工程与科学 2000年第1期22卷 86-88页

作者：胡贯荣谢美意华中理工大学计算机学院

可预测性和分布式实时 IPC是分布式实时应用的两个重要问题。本文探讨了可预测性的概念 ,提出了分布式实时 IPC的抽象模型 ,并分析影响分布式实时 IPC的主要因素 ,为设计分布式实时应用作一定的探讨。

关键词：期限可预测性分布式实时IPC 实时操作系统

快速协同浊点萃取-荧光分光光度法结合偏最小二乘测定水中2,4-二甲基苯酚

在线全文

学校读者我要写书评

暂无评论

分析试验室 2021年第9期40卷 1026-1030页

作者：姜勋刘炜婷谢美仪郝晓棠刘甜恬王梅广东药科大学公共卫生学院广州510310

建立了快速协同浊点萃取-荧光分光光度法结合偏最小二乘(PLS)测定水中2,4-二甲基苯酚(DMP)的方法。以聚乙二醇6000为萃取剂,乙腈为协同诱导剂,与无水Na_(2)SO_(4)共同作用,室温1 min内完成对DMP萃取,并采用荧光光度法测定目标分析物。... 详细信息

建立了快速协同浊点萃取-荧光分光光度法结合偏最小二乘(PLS)测定水中2,4-二甲基苯酚(DMP)的方法。以聚乙二醇6000为萃取剂,乙腈为协同诱导剂,与无水Na_(2)SO_(4)共同作用,室温1 min内完成对DMP萃取,并采用荧光光度法测定目标分析物。选择化学计量学中的PLS建模,以排除水样中主要干扰物苯酚的影响,实现对DMP的准确测定。结果表明,PLS建模时,提取2个主成分最佳,DMP分析结果的相对预报误差在可接受范围内。DMP的线性范围是0.10~3.0μg/mL,检出限(LOD)为3.4 ng/mL。该方法已用于环境水样中DM P的测定,加标回收率为99.4%~107%。

关键词：快速协同浊点萃取荧光分光光度法偏最小二乘法 2 4-二甲基苯酚

在线全文

学校读者我要写书评

暂无评论

基于虚拟机的存储过程设计与实现

计算机工程与应用 2004年第10期40卷 172-175页

作者：王元珍廖健谢美意华中科技大学计算机学院数据库与多媒体技术研究所武汉430074

存储过程在数据库管理系统中占有重要的地位。虚拟机为解释性语言提供了一套完整的运行环境接口。该文提出了一种基于虚拟机的实现存储过程的方法,并结合存储过程的特点介绍了一些实现细节。该方法已经应用到DM数据库管理系统之中。

关键词：存储过程虚拟机数据库管理系统

Multi-layer multi-pass friction rolling additive manufacturing of Al alloy:Toward complex large-scale high-performance components

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 425-438页

作者： Haibin Liu Run Hou Chenghao Wu Ruishan xie Shujun Chen College of Mechanical&Energy Engineering Beijing University of TechnologyBeijing 100124China Chongqing Research Institute of Beijing University of Technology Chongqing 401121China

At present,the emerging solid-phase friction-based additive manufacturing technology,including friction rolling additive man-ufacturing(FRAM),can only manufacture simple single-pass *** this study,multi-layer multi-pass FRAM-deposited alumin-um alloy samples were successfully prepared using a non-shoulder tool *** material flow behavior and microstructure of the over-lapped zone between adjacent layers and passes during multi-layer multi-pass FRAM deposition were studied using the hybrid 6061 and 5052 aluminum *** results showed that a mechanical interlocking structure was formed between the adjacent layers and the adja-cent passes in the overlapped center *** friction and rolling of the tool head led to different degrees of lateral flow and plastic deformation of the materials in the overlapped zone,which made the recrystallization degree in the left and right edge zones of the over-lapped zone the highest,followed by the overlapped center zone and the non-overlapped *** tensile strength of the overlapped zone exceeded 90%of that of the single-pass deposition *** is proved that although there are uneven grooves on the surface of the over-lapping area during multi-layer and multi-pass deposition,they can be filled by the flow of materials during the deposition of the next lay-er,thus ensuring the dense microstructure and excellent mechanical properties of the overlapping *** multi-layer multi-pass FRAM deposition overcomes the limitation of deposition width and lays the foundation for the future deposition of large-scale high-performance components.

关键词： aluminum alloy additive manufacturing solid-state friction stir welding multi-layer multi-pass

Superhydrophobic and corrosion-resistant siloxane-modified MgAl-LDHs coatings on magnesium alloy prepared under mild conditions

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 450-463页

作者： Wenxi Zhang Zhangzelong Zhuo Dan Xu Liang Wu Zhihui xie Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province College of Chemistry and Chemical EngineeringChina West Normal UniversityNanchong 637002China College of Materials Science and Engineering/National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China

We have developed a superhydrophobic and corrosion-resistant LDH-W/PFDTMS composite coating on the surface of Mg *** composite comprised a tungstate-intercalated(LDH-W)underlayer that was grown at low temperature(relative to hydrothermal reaction conditions)under atmospheric pressure and an outer polysiloxane layer created from a solution containing perfluorodecyltrimethoxysilane(PFDTMS)using a simple immersion *** successful intercalation of tungstate into the LDH phase and the following formation of the polysiloxane layer were confirmed through X-ray diffraction(XRD),Fourier transform infrared(FTIR)spectroscopy,and X-ray photoelectron spectroscopy(XPS).The corrosion resistance of the LDH-W film,both before and after the PFDTMS modification,was evaluated using electrochemical impedance spectroscopy(EIS),Tafel curves,and immersion *** results showed that Mg coated with LDH-W/PFDTMS exhibited significantly enhanced corrosion protection compared to the unmodified LDHW film,with no apparent signs of corrosion after exposure to 3.5wt%NaCl solution for 15 ***,the LDH-W/PFDTMS coating demonstrated superior superhydrophobicity and self-cleaning properties against water and several common beverages,as confirmed by static contact angle and water-repellency *** results offer valuable insights into preparing superhydrophobic and corrosion-resistant LDH-based composite coatings on Mg alloy surfaces under relatively mild reaction conditions.

关键词： Mg alloy corrosion coating layered double hydroxide

Unraveling the significance of cobalt on transformation kinetics,crystallography and impact toughness in high-strength steels

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 380-390页

作者： Yishuang Yu Jingxiao Zhao Xuelin Wang Hui Guo Zhenjia xie Chengjia Shang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

This work reveals the significant effects of cobalt(Co)on the microstructure and impact toughness of as-quenched highstrength steels by experimental characterizations and thermo-kinetic *** results show that the Co-bearing steel exhibits finer blocks and a lower ductile-brittle transition temperature than the steel without ***,the Co-bearing steel reveals higher transformation rates at the intermediate stage with bainite volume fraction ranging from around 0.1 to *** improved impact toughness of the Co-bearing steel results from the higher dense block boundaries dominated by the V1/V2 variant ***,the addition of Co induces a larger transformation driving force and a lower bainite start temperature(BS),thereby contributing to the refinement of blocks and the increase of the V1/V2 variant *** findings would be instructive for the composition,microstructure design,and property optimization of high-strength steels.

关键词： high-strength steel cobalt transformation kinetics crystallography impact toughness